Keto Rhubarb Dump Cake That’s Actually Worth Making (No Fuss, No Sugar)

If you’ve got rhubarb growing like weeds out back or spotted it at the market and thought, what am I supposed to do with this?, you’re not alone. Rhubarb looks like red celery, tastes tart as heck, and somehow ends up in some of the best old-school desserts. And let me just say it—if you’re eating low carb, you don’t have to miss out. This Keto Rhubarb Dump Cake nails that tangy-sweet vibe without needing sugar or flour or any of that usual trouble.

Let’s be real, most “keto desserts” taste either dry, eggy, or like you’re being punished for trying to be healthy. But not this one. This is that cozy rhubarb snacking cake you didn’t know you needed, the kind that feels like grandma made it but with zero sugar crashes.

This is a mix-it-and-go style dessert. Just dump it in the pan and bake. No mixer, no drama.

Why Dump Cakes Work (Especially Low Carb Ones)

You know how some desserts take forever? Not this. A dump cake is the lazy person’s dream. You throw fruit in a pan, pour a mix on top, drizzle butter or coconut oil, and you’re done. Think of it like a cake-cobbler hybrid. Only this one’s sugar free and low carb, using keto cake mix and a little bit of sweetener that won’t spike anything.

There’s a reason sugar free dump cake recipes are all over Pinterest now. They’re not only fast, but they let you enjoy baked desserts again without feeling like you’ve fallen off the wagon.

Ingredients You’ll Need

Here’s what you’ll want to grab for this rhubarb dump cake with cake mix:

  • 3 cups chopped rhubarb (fresh or frozen, doesn’t matter—just thaw if frozen)

  • 1/2 cup chopped strawberries (optional but adds that classic flavor combo)

  • 2 tbsp sugar-free strawberry or raspberry gelatin (adds sweetness + binds the fruit, like in rhubarb jello cake or rhubarb strawberry dump cake with jello)

  • 1/3 cup allulose or monk fruit blend (tastes most like sugar)

  • 1 tsp vanilla extract

  • 1/2 tsp cinnamon (trust me, don’t skip this)

  • 1 packet of keto vanilla cake mix (this is key for keto cake mix desserts)

  • 1/3 cup melted butter or coconut oil

You’ll also need a baking dish, about 9×13 or something close.

How To Make Keto Rhubarb Dump Cake (Step-by-Step)

Step 1: Preheat and Prep Your Pan

Set your oven to 350°F (175°C). Grab a 9×13 inch baking dish (glass or ceramic works best). Lightly grease it with butter or non-stick spray so nothing sticks to the bottom.

Step 2: Mix Up the Fruit Layer

In a large mixing bowl (or honestly, right in the baking dish if you want fewer dishes), combine 3 cups of chopped rhubarb and 1/2 cup of chopped strawberries.
Sprinkle 2 tablespoons of sugar-free gelatin over the fruit—this helps create that gooey, almost pie-filling vibe.
Add 1/3 cup of your chosen sweetener (like allulose or a monk fruit blend), 1 teaspoon of vanilla extract, and 1/2 teaspoon of cinnamon.
Stir everything together until the fruit is coated and looks glossy.

Step 3: Dump It In

If you mixed in a bowl, dump that fruit mixture evenly into your greased baking dish. Spread it out so the bottom is covered and the fruit is mostly in a single layer.

Step 4: Add the Cake Mix Layer

Take your dry keto vanilla cake mix and sprinkle it directly over the fruit. Spread it out with your hand or a spoon so there’s a nice, even layer across the top.
Important: Don’t mix the cake layer into the fruit. Just let it sit on top—it bakes into a crust all on its own.

Step 5: Pour On the Melted Butter or Oil

Melt 1/3 cup of butter or coconut oil. Slowly drizzle it over the entire surface of the cake mix. You want to moisten as much of the top layer as possible. It’s okay if some dry spots remain—they’ll bake up crispy.

Step 6: Bake It

Slide the dish into the oven and bake for 35 to 40 minutes. You’re looking for a golden-brown top and bubbling edges where the rhubarb juice starts to peek through.
The smell? Unreal.

Step 7: Let It Cool and Set

Take the dish out of the oven and let it rest for at least 10 to 15 minutes. It’s tempting to dig in right away, but trust—it thickens as it sits and becomes way easier to scoop.

Can You Make This in a Crockpot?

Oh, absolutely. Rhubarb crockpot dump cake is even lazier. Just follow the same layering steps in your slow cooker, cover, and cook on high for about 2 hours or low for 3–4. Don’t peek too much—it slows everything down.

What If You Can’t Find Rhubarb?

Got no rhubarb? No worries. This doubles as a keto apple dump cake too. Just sub in chopped chayote squash (weird, I know, but it tastes like apples when baked with cinnamon and sweetener).

Still want fruit but not into squash? Try raspberries or blueberries. Anything low carb works here. Even mixing a bit of each turns this into a kind of keto fruit dessert buffet.

Other Keto Baked Desserts to Try If You’re Obsessed With This

Once you’ve tried this and realized keto desserts don’t have to suck, you’ll probably want more like it. So here are some no-fail low carb baked desserts that won’t make your eyeballs roll:

  • Keto apple dump cake (again, chayote or zucchini + cinnamon is the trick)

  • Cake mix brownies made from the same keto cake mix, just add cocoa and eggs

  • Old fashioned rhubarb pudding cake with almond flour and coconut milk instead of regular batter

  • Rhubarb upside down cake with jello — gelatin helps get that gooey fruity layer just right

  • Easy rhubarb cake made in muffin tins for snack-size bites

All of these are based on keeping sugar out, carbs low, and taste real.

Rhubarb Cake Mix Recipes Without the Weird Ingredients

You don’t need xanthan gum or 15 eggs to make rhubarb cake recipes easy and actually edible. Just stick to basics. Keto cake mix + real rhubarb + a little gelatin for texture. That’s the trick. For a twist, make mini versions of this in ramekins—perfect for that single-serve cake craving.

Want it crispier on top? Sprinkle crushed pecans or almond flour mixed with cinnamon before baking. Think rhubarb crisp meets cake mix dessert recipes.

Storage & Reheating (If You Don’t Eat It All at Once)

Store leftovers in the fridge for up to 5 days. Reheat in the microwave for about 30 seconds to warm it up again. Honestly, this thing tastes even better cold the next day. Like rhubarb pudding cake-meets-breakfast vibe.

You can freeze it too. Slice into squares and freeze individually so you’re not tempted to eat the whole tray.

Pair It Like a Pro

Want to make this feel like a full dessert? Serve with:

  • Whipped cream (make your own with heavy cream + sweetener)

  • Low carb vanilla ice cream

  • Greek yogurt (for a fake cheesecake feel)

Don’t go overboard though—this cake’s rich enough already.

Tips For Making Dump Cakes Work (Low Carb Style)

  • Don’t stir the layers. It bakes right if you leave them alone.

  • Melted fat is key. Don’t skip the butter or oil—it’s what makes that crispy top.

  • Gelatin helps the fruit not get soggy. Use sugar-free jello for the classic style.

  • Always taste your fruit. If your rhubarb is really tart, go up a bit on sweetener.

  • Bake long enough. The top needs time to get that nice golden finish.

Conclusion

This isn’t one of those desserts you make once and forget. This one makes it into the regular rotation. It’s easy, cheap if you’ve got rhubarb growing in your yard, and actually feels like dessert—not just a weird keto experiment.

Whether you’re already deep into low carb dump cake recipes or just starting to test the sugar free life, this cake’s got something going for it. It’s the kind of low carb keto dessert you’ll pull out when people say, “I miss real dessert.” And you’ll just smile.

Bake it once, and you’ll be looking at your rhubarb like it’s cake gold.

Print

Keto Rhubarb Dump Cake Recipe

This keto rhubarb dump cake is the easiest low carb dessert for summer. No sugar, no mixing bowls—just dump the ingredients in a dish and bake. Sweet, tart, buttery, and baked golden brown. A perfect keto fruit dessert for anyone on a low carb or keto diet.

  • Author: Jane Summerfield
  • Prep Time: 10 minutes
  • Cook Time: 40 minutes
  • Total Time: 50 minutes
  • Yield: 8 servings 1x
  • Category: Dessert
  • Method: Baking
  • Cuisine: American, Keto, Low-Carb
  • Diet: Gluten Free

Ingredients

Scale
  • 3 cups chopped rhubarb (fresh or frozen)

  • 1/2 cup chopped strawberries (optional but tasty)

  • 2 tbsp sugar-free strawberry or raspberry gelatin

  • 1/3 cup allulose or monk fruit sweetener

  • 1 tsp vanilla extract

  • 1/2 tsp cinnamon

  • 1 packet keto vanilla cake mix

  • 1/3 cup melted butter or coconut oil

Instructions

  1. Preheat oven to 350°F and lightly grease a 9×13 baking dish.

  2. In the dish, toss rhubarb and strawberries with gelatin, sweetener, vanilla, and cinnamon.

  3. Sprinkle the dry keto cake mix evenly over the fruit mixture—don’t stir.

  4. Drizzle melted butter or coconut oil on top, covering most of the cake mix.

  5. Bake for 35–40 minutes or until the top is golden brown and fruit is bubbling at the edges.

  6. Let cool 10–15 minutes before serving.

Notes

  • You can skip the strawberries or swap for other low carb fruits like raspberries.

  • To make in a slow cooker, cook on high for 2 hours or low for 3–4 hours.

  • For a crispier topping, sprinkle chopped nuts or almond flour over the cake mix before baking.

Nutrition

  • Serving Size: 1 serving
  • Calories: 195 Sugar: 1g Sodium: 210mg Fat: 15g Saturated Fat: 6g Unsaturated Fat: 9g Trans Fat: 0g Carbohydrates: 9g Fiber: 4g Protein: 4g Cholesterol: 20mg

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