Keto Portobello Steaks with Chimichurri (That Even Meat Lovers Will Crave)

I’ve cooked a lot of steak recipes with chimichurri over the years. Thick cuts, thin slices, even steak bites drowned in herby sauce. But when I decided to lay off the meat for a while, I found myself staring down a big portobello mushroom, thinking… could this really take the place of steak?

Turns out—yes. With the right prep, good olive oil, and a bold chimichurri sauce recipe, these mushroom steaks hit hard. They’re smoky, juicy, a little chewy, and they pick up flavor like crazy. It’s one of those recipes that even meat-eaters don’t complain about. Especially when you throw that chimichurri on top.

Let’s walk through it, step by step. Nothing fancy. Just honest food, made well.

What You’ll Need For this Keto Portobello Steaks Recipe

For the Portobello Steaks:

• 4 large portobello mushrooms (wiped clean, stems removed)

• 2 tbsp olive oil

• Salt and pepper

• 1 tsp garlic powder

• 1 tsp smoked paprika

• A grill pan or cast iron skillet

For the Chimichurri Sauce:

• 1 cup fresh parsley (finely chopped)

• 3 cloves garlic (minced)

• 2 tbsp red wine vinegar

• ½ cup olive oil

• 1 tsp dried oregano

• ½ tsp red pepper flakes (optional)

• Salt to taste

Step-by-Step Cooking Instructions

1. Prep the Mushrooms Like a Pro

The first trick with mushroom steaks? Don’t soak them. Mushrooms are like little sponges, and if you wash them under running water, they get mushy when you cook them. Just use a damp paper towel to wipe them clean. Pop out the stems and scrape the dark gills if they bother you (I leave them).

Lay the mushrooms down and drizzle with olive oil. Sprinkle salt, pepper, garlic powder, and smoked paprika on both sides. Rub everything in. Let them sit for 10–15 minutes while you make the chimichurri.

2. Make Chimichurri (It’s Easier Than You Think)

This is where flavor lives.

Chop the parsley and garlic real fine. Don’t use a food processor—you want texture. Toss it in a bowl with red wine vinegar, oregano, red pepper flakes, olive oil, and salt. Stir well. Taste it. If it needs more vinegar or salt, add it. Some people like it with more garlic. Up to you.

This is the same sauce I use for steak bites with chimichurri sauce, and it works every time. It keeps in the fridge for a few days, too—great over eggs, roasted veggies, or grilled meat.

3. Sear the Mushrooms

Heat a cast iron skillet or grill pan on medium-high. No oil needed—the mushrooms already have some on them. Once the pan is hot, lay the mushrooms down, gill side first. Press them with a spatula for a nice sear. Cook 4–5 minutes on each side.

They should shrink and brown. The edges will char just a bit—that’s what you want. That’s where the meatiness shows up.

Once they’re tender but still hold their shape, they’re done.

How to Serve It

Slice the mushrooms thick like steak. Spoon chimichurri on top. Eat right away.

You can serve this solo as a light dinner, or throw it on a plate next to cauliflower mash, grilled zucchini, or even a handful of roasted nuts if you need something crunchy. These also make killer keto meat appetizers when sliced thin and laid over low-carb crackers or roasted eggplant rounds.

Why It Works (Yes, Even for Meat-Lovers)

This recipe takes notes from all my favorite steak dishes: steak bites recipe, steak and chimichurri, even beef tenderloin with chimichurri sauce. The method’s the same—hot sear, bold sauce, simple seasoning.

But instead of meat, you’ve got a mushroom doing all the heavy lifting.

It’s got that bite. That chew. And most importantly, it doesn’t pretend to be something it’s not. Portobellos are earthy and strong enough to stand next to garlic, parsley, and vinegar without getting lost.

It’s why I’ve even served these at parties. And folks? They disappeared faster than the actual steak crostini chimichurri bites I made that same night.

Flavor Tips That Make a Big Difference

• Don’t skip the paprika. It brings smoke. If you’ve got smoked salt, even better.

• Let the mushrooms sit in the seasoning. A little time = deeper flavor.

• Grill them outside. If you’ve got a grill, use it. Fire plus mushrooms equals magic.

• Make extra chimichurri. This stuff gets better overnight and works with anything. Eggs, shrimp, even spooned onto burgers or chicken.

Portobello Steaks with Chimichurri Variations You Can Try

This base recipe is solid. But once you’ve made it once, there’s room to play:

• Chimichurri Steak Bites (Vegetarian): Slice the portobellos into chunks before searing, then toss in chimichurri like traditional steak bites with chimichurri sauce. Serve on toothpicks for keto meat appetizers that aren’t meat.

• Portobello Crostini with Chimichurri: Thinly slice grilled mushrooms and lay on toasted keto bread or grilled eggplant slices. Top with chimichurri. It’s a nod to steak crostini chimichurri but meatless.

• Add Cheese: A thin shaving of Manchego or Parmesan adds saltiness without adding too many carbs.

Meal Prepping This Recipe

You can grill the mushrooms ahead of time, store them in the fridge, then warm them up in a pan or microwave. The texture holds. Chimichurri can sit in the fridge 3–4 days no problem. Just give it a stir before using again.

One night, I packed these mushrooms and sauce in a lunchbox, brought it to work, and ate it cold like leftover steak salad. Honestly? Still amazing.

Who’s This For?

• Anyone doing keto and tired of bacon-wrapped everything.

• Vegetarians who want something that feels hearty.

• Meat-eaters trying to cut back but not ready to eat “rabbit food.”

• Folks looking for fast dinner ideas that don’t involve 47 ingredients or an air fryer.

• Anyone throwing a party and wants a few easy meat appetizers that feel a bit elevated but still simple.

Conclusion

You won’t miss the steak, I swear. I’ve served these next to actual steak bites recipe dishes, and people go back for the mushrooms just as often. It’s about texture, fat, salt, and acid—and this recipe nails all four.

It’s not trying to fake beef. It’s giving mushrooms the treatment steak usually gets. And guess what? They earn it.

So the next time you’re thumbing through recipes, wondering what to make with that giant mushroom you bought on a whim… make this. Simple, fast, flavor-packed, and yes—100% keto.

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