If you’ve never tried a rhubarb dump cake, you’re in for a treat. This effortless dessert combines tart rhubarb, sweet cake mix, and a buttery topping into one mouthwatering masterpiece. The best part? You don’t need to mix a thing—just dump, layer, and bake.
It’s the ultimate easy rhubarb dessert, perfect for last-minute guests, potlucks, or when your rhubarb plant is going wild. Minimal prep, maximum flavor, and no fancy equipment required.
Let’s make this crowd-pleaser in under 10 minutes of prep time.
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Rhubarb Dump Cake
Ingredients
Equipment
Method
- Preheat oven to 350°F (175°C). Grease a 9×13 inch baking dish.
- Spread chopped rhubarb evenly over the bottom of the dish.
- Sprinkle granulated sugar evenly over the rhubarb.
- Sprinkle dry yellow cake mix evenly over the sugar layer. Do not stir.
- Pour water or juice evenly over the top, then drizzle melted butter across the surface.
- Bake uncovered for 45–50 minutes, or until golden brown and bubbling. Let cool slightly before serving.
Notes
What Is a rhubarb dump cake recipe?
A dump cake is a simple dessert where ingredients are literally dumped into the baking dish—no mixing bowls, electric mixers, or stress. Think of it as the lazy baker’s version of a crisp or cobbler, but with cake mix doing the heavy lifting.
This rhubarb dump cake recipe uses just a few pantry staples: chopped rhubarb, sugar, boxed cake mix, and melted butter. The result is a gooey, golden-topped dessert with sweet-tart fruit bubbling underneath.
Why You’ll Love This Rhubarb Dump Cake
- Ridiculously easy – Just layer and bake.
- No-mess recipe – All the magic happens in one pan.
- Sweet and tangy – Rhubarb’s tartness balances beautifully with the rich, buttery cake topping.
- Perfect for spring and summer – Ideal when rhubarb is in season.
- Customizable – Add strawberries, swap the cake flavor, or top with whipped cream or vanilla ice cream.
Looking for more no-fuss desserts? Try our 3 Ingredient Chocolate Yogurt Cake.
Ingredients You’ll Need
Ingredient | Amount | Notes |
---|---|---|
Fresh rhubarb | 4 cups, chopped | Cut into ½-inch pieces |
Granulated sugar | ¾ cup | Balances rhubarb’s tartness |
Boxed cake mix | 1 box (vanilla or white) | Yellow cake mix works well too |
Unsalted butter | ½ cup (1 stick), melted | Adds rich flavor and browning |
Optional toppings | Ice cream or whipped cream | For serving |
Pro Tip: If using frozen rhubarb, thaw and drain excess moisture first.
How to Make Rhubarb Dump Cake (Step-by-Step)
Step 1: Preheat and prep
Preheat your oven to 350°F (175°C). Lightly grease a 9×13-inch baking dish or coat with cooking spray.
Step 2: Layer rhubarb and sugar
Place the chopped rhubarb in the dish, spreading it out evenly to cover the base. Sprinkle the sugar directly over the rhubarb to help draw out its juices and tame its tartness.
Step 3: Add the cake mix
Without stirring, sprinkle the dry cake mix over the rhubarb and sugar. Use a spoon to spread it evenly across the surface—do not mix it in.
Step 4: Pour the melted butter
Drizzle the melted butter slowly over the entire surface of the cake mix, covering as much as possible. This helps create the golden crust while allowing the bottom to turn soft and gooey.

Step 5: Bake
Bake for 40–45 minutes or until the top is golden and bubbly, and the edges are slightly crisp.
Let the cake rest for 10–15 minutes before serving—it’ll firm up slightly as it cools.
Flavor Variations to Try
- Strawberry Rhubarb Dump Cake: Mix 2 cups rhubarb with 2 cups chopped strawberries.
- Lemon Rhubarb: Use lemon cake mix and add a bit of lemon zest for brightness.
- Spiced Rhubarb: Add a sprinkle of cinnamon or nutmeg before the cake mix.
- Coconut Rhubarb: Top with shredded coconut before baking for tropical vibes.
- Rhubarb Peach Dump Cake: Swap half the rhubarb with sliced canned peaches (drained).
Want another fruity idea? Don’t miss our Rhubarb Cookies Recipe.
Tips for Dump Cake Success
- Even butter distribution: Drizzle melted butter slowly and evenly. Any dry cake mix left uncoated may not bake well.
- No mixing needed: Resist the urge to stir—layering is key!
- Let it rest: The cake firms up as it cools and becomes easier to slice or scoop.
- Serve warm or chilled: Delicious either way, especially with a cold scoop of vanilla ice cream.
Storage & Make-Ahead Notes
Method | Duration | Notes |
---|---|---|
Room Temperature | 1 day | Best if served the same day |
Refrigerator | Up to 4 days | Store in airtight container |
Freezer | Up to 2 months | Freeze in individual portions for easy reheating |
To reheat, microwave a serving for 30–45 seconds or warm in a 300°F oven for 10 minutes.
Serving Suggestions
This rhubarb dump cake is best enjoyed:
- Warm with ice cream – Vanilla or cinnamon ice cream are top picks
- Chilled with whipped cream – Great for next-day leftovers
- With morning coffee – Yes, it doubles as a sweet breakfast treat
- Topped with yogurt – A lighter way to enjoy it any time of day
Looking for a savory spring dish? Try our Ground Beef and Zucchini Skillet for dinner before this dessert.

FAQs – Rhubarb Dump Cake Recipe
Can I use frozen rhubarb in this recipe?
Yes. Just make sure it’s fully thawed and drained so your cake doesn’t turn watery.
Does this work with gluten-free cake mix?
Absolutely! Use your favorite gluten-free boxed cake mix and follow the same instructions.
Can I reduce the sugar?
Yes, you can use ½ cup sugar if your rhubarb is on the sweeter side or you’re using a sweet fruit combo.
What kind of cake mix works best?
Vanilla, white, or yellow cake mix all work great. For something bolder, try lemon or spice cake mix.
Can I make this ahead of time?
yes, Bake it the night before and warm it up before serving. It actually tastes better after sitting!
Conclusion
If you want a no-fuss dessert that celebrates spring fruit and takes almost zero effort, this rhubarb dump cake recipe is your go-to. With its gooey center, buttery crust, and just the right amount of tartness, it’s everything a dump cake should be—simple, satisfying, and totally crave-worthy.
Make it once, and you’ll be adding it to your regular dessert rotation every rhubarb season.
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