Keto Poblano Chicken Mac and Cheese (Low Carb, Big Flavor)

If mac and cheese and a chicken fajita had a quiet weekend together, they’d come back as this casserole. It’s rich, creamy, a little smoky, with a gentle pepper warmth that doesn’t knock your socks off. The “mac” is cauliflower, the sauce is a silky cheese hug, and the chicken keeps it filling without pushing carbs up. Pinterest folks love a cozy bake that slices clean and looks gooey in photos, and this one delivers.

I fell for this dish the night I tried to make dinner with only what was sitting around: leftover rotisserie chicken, two poblanos that were starting to wrinkle, a head of cauliflower, and a scary amount of cheese. I tossed it together, crossed fingers, and—wow. Since then I’ve tweaked the steps so it’s weeknight simple, meal prep friendly, and fully keto.

Below is everything you need. Plain talk, no fluff, just good food.

Why Make Keto Poblano Chicken Mac and Cheese?

• Real mac vibes, fewer carbs: Cauliflower florets mimic pasta shells when cooked to tender-firm. They hold sauce and don’t turn watery if you treat them right.
• Poblano magic: Poblanos are mild. Roasting or sautéing them brings a light smokiness that makes the cheese taste deeper, not hotter.
• Three-cheese blend: Sharp cheddar for bite, Monterey Jack for melt, a little cream cheese for body. Smooth sauce, no grainy mess.
• One pan finish: Build the sauce on the stove, fold in chicken and cauliflower, bake till bubbly with a crisp topping. Great for photos and leftovers.

Ingredients (serves 6, generous)

For the “mac” and chicken

• 1 large head cauliflower (about 2 to 2.25 lb), cut into small bite-size florets
• 2 medium poblano peppers, seeded and sliced in thin strips
• 2 cups cooked chicken, shredded or diced (rotisserie is fine)
• 2 tbsp olive oil or butter
• 1 tsp kosher salt, plus more to taste
• 1/2 tsp black pepper
• 1/2 tsp smoked paprika (optional but lovely)
• 1/2 tsp garlic powder
• 1/2 tsp onion powder

For the cheese sauce

• 2 tbsp butter
• 3 cloves garlic, minced (or 1 tsp garlic powder if you must)
• 1.5 cups heavy cream
• 4 oz cream cheese, softened and cubed
• 2 tsp Dijon mustard (rounds out the cheese, doesn’t taste “mustardy”)
• 1/4 tsp xanthan gum (optional thickener; use if you want extra cling)
• 2 cups shredded sharp cheddar
• 1 cup shredded Monterey Jack (or mozzarella)
• Salt to taste

Crunchy topping (low-carb)

• 1/2 cup crushed pork rinds or 1/3 cup almond flour
• 1/2 cup shredded cheddar or parmesan
• 1 tbsp melted butter
• Pinch of smoked paprika

Finish

• Chopped cilantro or green onion for garnish
• Lime wedges (squeeze on top gives it pop)

Note: Carb counts will vary by brand. Poblanos are mild; if your store swapped in Anaheim peppers by mistake, you’re still fine.

Tools you’ll need

• Large pot for blanching cauliflower
• Colander
• Large skillet or sauté pan
• 9×13 inch baking dish (ceramic or metal)
• Whisk and wooden spoon
• Chef’s knife and cutting board
• Oven preheated to 375°F / 190°C

Step-by-step instructions for Cooking Keto Poblano Chicken Mac & Cheese

1) Preheat and prep

Set oven to 375°F. Butter or spray the baking dish. Bring a big pot of salted water to a rolling boil.

2) Blanch the cauliflower

Add florets. Cook 3–4 minutes till just tender on the outside but still with a little snap. You’re not cooking them through here, just taking the raw edge off. Drain well, then spread on a towel-lined sheet for 5–10 minutes to steam off moisture. This little pause keeps the casserole from getting watery later.

3) Cook poblanos

Heat 2 tbsp oil/butter in a large skillet over medium-high. Add poblano strips with a pinch of salt. Sauté 5–7 minutes till softened with a few char kisses. Stir in paprika, garlic powder, onion powder, and black pepper during the last minute. Transfer peppers to a plate.

4) Make the cheese sauce

In the same skillet, lower heat to medium. Add 2 tbsp butter. When melted, add minced garlic, cook 30 seconds till fragrant. Pour in heavy cream and bring to a bare simmer—tiny bubbles at the edges. Whisk in cream cheese cubes and Dijon until smooth.

If using xanthan gum, sprinkle very lightly over the surface while whisking. It thickens fast; go slow. Turn heat to low and whisk in cheddar and Monterey Jack by handfuls, letting each handful melt before adding the next. Taste and add salt if needed. The sauce should coat a spoon like custard.

5) Combine

Fold the chicken and the sautéed poblanos into the sauce. Gently fold in the dry cauliflower florets so they’re well coated but not smashed. Spoon everything into your baking dish and even the top.

6) Topping

Mix crushed pork rinds (or almond flour), shredded cheddar/parmesan, melted butter, and a pinch of smoked paprika. Scatter evenly over the casserole.

7) Bake

Bake 18–22 minutes till bubbling at the edges and the topping is lightly browned. If you want extra color, broil 1–2 minutes, watching close so it doesn’t burn.

8) Rest and serve

Let it stand 8–10 minutes. This helps the sauce set so you get clean scoops. Garnish with cilantro or green onion. A tiny squeeze of lime over each serving wakes everything up.

Flavor notes and swaps

• Heat level: Poblanos are mild, about 1,000–1,500 Scoville. Want more kick? Add a minced jalapeño with the poblanos or a dash of chipotle powder in the sauce.
• Cheese choices: Cheddar + Jack is reliable. Pepper Jack for a little heat, Gruyère for fancy vibes, or a touch of smoked gouda if you want campfire tone.
• No xanthan gum: Skip it. Reduce the cream by 2 tbsp and simmer the sauce 2 more minutes to thicken.
• No pork rinds: Use almond flour mixed with parmesan and butter. Want nut-free? Use sesame flour or just more cheese on top.
• Chicken options: Thigh meat stays juicy. Leftover turkey works too. If starting with raw chicken, dice 1 lb, sauté in the pan before the peppers, season with salt and pepper, then proceed.

Timing breakdown

• Prep and chopping: 15 minutes
• Blanch cauliflower + drain: 10–12 minutes
• Sauté poblanos: 7 minutes
• Cheese sauce: 10 minutes
• Bake: 20 minutes
• Rest: 10 minutes

Total: about 60–65 minutes, hands-on less than half.

How to keep cauliflower from getting watery

 

This part matters. Cauliflower holds water like a sponge. Here’s how we avoid that soupy bottom:

• Cut florets small and even so they blanch fast and don’t go mushy.
• Salt your blanching water properly (like pasta water).
• Blanch only 3–4 minutes. You’ll finish in the oven.
• Drain and spread the florets to steam off. Don’t throw them in the dish while wet.
• Sauce should be a touch thicker than you think. It loosens slightly in the heat.

Follow those and your “mac” will eat like pasta, not like soup.

Make-ahead and meal prep

• Assemble now, bake later: Build the casserole, cover tight, and refrigerate up to 24 hours. Bake from cold at 350°F for about 30–35 minutes till hot and bubbly (foil for the first 15 minutes, then remove).
• Freezer: Assemble without the crunchy topping. Wrap well and freeze up to 2 months. Thaw in the fridge overnight. Add topping and bake 35–40 minutes at 350°F.
• Leftovers: Cool, cover, and refrigerate up to 4 days. Reheat covered at 325°F or microwave in 45-second bursts. If it tightens, stir in a splash of cream.

Nutrition snapshot (estimate per serving, 1/6 of pan)

• Calories: ~520
• Net carbs: ~7–9 g (depends on cauliflower size and cheese brand)
• Fat: ~38 g
• Protein: ~31 g
• Fiber: ~3 g
  These are rough numbers, not medical advice. If you track, plug your exact brands into your app.

Serving ideas

• Fajita bowl style: Spoon into a bowl with shredded lettuce, avocado slices, a spoon of salsa verde, and a lime wedge.
• Game day bites: Bake in mini ramekins for tidy servings.
• Brunch plate: Top a scoop with a fried egg. Sounds odd, tastes great.
• Tex-Mex mood: Dust with chili powder and add a few pickled jalapeño rings on top.

What poblanos bring to the party

Poblanos sit in a sweet spot between bell peppers and jalapeños. They have a darker, almost earthy green flavor. When you sauté or roast them, they get soft and just a little smoky. That tone cuts through rich cheese so it doesn’t feel heavy after two bites. If you can only find them roasted in a can, drain well and pat dry, then add them right after the cream cheese melts in the sauce.

Troubleshooting (stuff that happens, fast fixes)

• Grainy cheese sauce: Heat was too high or cheese went in too fast. Keep the sauce below a boil and add cheese by handfuls. A splash more cream and steady whisking can smooth it out.
• Watery bottom: Cauliflower was too wet or under drained. Next time spread to cool longer. For this pan, stir, add a few minutes under broiler to evaporate, and serve.
• Too thick: Stir in warm cream, little by little, until it loosens.
• Too mild: Add chipotle powder or hot sauce at the table.
• Bland bite: Check your salt. Cheese is salty but cream and cauliflower mute it. Taste your sauce before baking.

Two quick versions

Weeknight shortcut
Use pre-riced cauliflower (steam-in-bag), but don’t overcook it. Drain well in a sieve and press out extra moisture with a spoon. You lose the “shell” vibe but gain speed. Sauce and bake as written.

Sheet-pan hack
Roast cauliflower and poblano strips together on a sheet at 425°F with oil, salt, paprika, 18 minutes till edges brown. Meanwhile make the sauce. Fold roasted veg into sauce with chicken, top, bake 10 minutes to marry. Roasted flavor gets louder.

Make it your style

• Bacon ranch: Add 6 slices cooked crumbled bacon and 1 tsp dry ranch seasoning to the sauce.
• Green chile: Swap poblanos for roasted Hatch chiles when in season.
• BBQ-ish: Stir 1 tsp smoked paprika + 1 tsp Worcestershire into the sauce. Finish with a tiny drizzle of sugar-free BBQ sauce on each portion.
• Broccoli swap: Half cauliflower, half broccoli. Kids tend to eat the green trees when they’re covered in cheese.
• Extra protein: Add a can of shredded chicken breast (well drained) along with thigh meat for a bigger pan without more carbs.

Pantry notes and brand tips

• Cream cheese: Let it warm a bit. Cold cubes fight you and lump up.
• Cheddar: Buy a block and shred. Pre-shredded is ok, but anti-caking powders can dull the melt.
• Pork rinds: Plain or lightly salted work best. Flavored ones can take over.
• Dijon: A small spoon wakes cheese sauces. You won’t taste “mustard,” promise.
• Xanthan gum: Use a tiny sprinkle. More than 1/4 tsp and the sauce can turn gloopy.

Safety and storage

Cool leftovers within 2 hours. Store in shallow containers so they chill fast. Reheat to 165°F in the center. If freezing, wrap tight to avoid freezer stink. Label the date; future you will thank you.

Step-by-step photo notes (how I plate it)

For Pinterest shots, scoop with a big spoon, let it stretch, then use a spatula to set the portion down so you see cheese strands. Sprinkle fresh cilantro and a few thin poblano rings on top, then a tiny shine of melted butter on the crust so it glows. A lime wedge on the side makes the green pop against the creamy bake.

What to serve with it (low carb sides)

• Simple cucumber tomato salad with lime and olive oil
• Buttered green beans with toasted almonds
• Shredded cabbage slaw, dressed light
• Sliced avocado with coarse salt and a pinch of chili powder

Cost check (approx, US grocery pricing)

• Cauliflower head: $3–4
• Poblanos: $1.50–2
• Chicken: $4–6 (using leftovers lowers cost)
• Dairy + cheese: $7–10
• Pantry items and topping: $2–3

So about $18–24 for 6 big servings, and very filling. For meal prep, that’s a win.

Step-by-step recap (short version)

• Blanch cauliflower 3–4 min, drain, spread to dry.
• Sauté poblanos 5–7 min with seasonings.
• Make cream cheese sauce with cream, Dijon; melt in cheddar + Jack.
• Fold in chicken, poblanos, then cauliflower.
• Top with pork rind (or almond flour) mix.
• Bake 18–22 min at 375°F, rest 10. Garnish and serve.

Personal notes from my kitchen

 

First time I made this, I only had mozzarella and a sad heel of cheddar. Sauce was floppy, still tasted great. The poblano lift saved it. Next try, I added Dijon and cream cheese, and it clicked. Now I grate cheddar fresh and I don’t skip the brief rest after baking. That pause is where the sauce settles in the gaps and you get that restaurant-style scoop. Also, the lime wedge… it sounds extra, but it’s not. Cheese plus a squeeze of acid is balance in a bite.

Frequently made mistakes (so you can avoid them)

• Overcooking the cauliflower during blanching. Keep it short.
• Dumping cold cheese into hot cream all at once. Add in stages.
• Skipping the dry step after blanching. Moisture ruins texture.
• Too much xanthan gum. A dusting is enough.
• Baking too long. You want bubbling and light brown, not a dry top.

Scale it up or down

• For 4 servings: Use 3/4 of everything, bake in an 8×8 dish, start checking at 15 minutes.
• For a crowd (12 servings): Double all ingredients, use two 9×13 dishes or one deep roasting pan, bake 25–30 minutes.

Keto notes

• This dish fits standard keto macros when portioned as written.
• If you’re strict, skip onion powder and use fresh green onion on top only.
• Keep an eye on cheese brands; some add starch in pre-shreds. Blocks are cleaner.

Screen short-friendly ingredient list

• Cauliflower (1 large)
• Poblanos (2)
• Cooked chicken (2 cups)
• Heavy cream (1.5 cups)
• Cream cheese (4 oz)
• Sharp cheddar (2.5 cups total counting topping)
• Monterey Jack (1 cup)
• Dijon (2 tsp)
• Butter (3 tbsp)
• Garlic (3 cloves)
• Pork rinds or almond flour (1/2 cup or 1/3 cup)
• Spices: kosher salt, black pepper, smoked paprika, garlic powder, onion powder
• Optional: xanthan gum, cilantro/green onion, lime

Stick this in your phone notes. Grocery trip gets easy.

Conclusion

 

Keto Poblano Chicken Mac & Cheese hits that comfort note without the carb hangover. It tastes like you cheated but you didn’t. The poblano warmth keeps things interesting, the sauce is glossy, and the top has a little crunch so each forkful has layers. Make it once and it slides into the regular rotation. If your people like things spicier, pass hot sauce at the table and call it done.

Bake it tonight, let it rest, then take that first scoop. If you don’t hear a small happy sigh from the table, I owe you a virtual high five.

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