This easy rhubarb dump cake recipe combines 5 cups of tart rhubarb, sweet strawberry gelatin, yellow cake mix, water, and melted butter in a greased 13 × 9-inch baking dish. With only 10–15 minutes of preparation and 45–50 minutes in a 350°F (175°C) oven, it creates a bubbling fruit dessert with a golden, buttery topping and about 12 servings.
The best part is that there is no mixing, rolling, or complicated pastry work. The rhubarb softens beneath the cake mix while its juices mingle with strawberry flavor, and the butter helps form a crisp, tender topping that is especially delicious served warm with vanilla ice cream or whipped cream.
Jump to RecipeWhy You’ll Love This Recipe
This rhubarb dump cake is the kind of dessert that looks and tastes impressive without demanding much time in the kitchen. The ingredients are layered directly in one baking dish, so there is no separate bowl for cake batter and very little cleanup afterward.
Every bite offers a pleasing contrast. The rhubarb becomes soft and jammy, the strawberry gelatin adds fruity sweetness and rosy color, and the yellow cake mix bakes into a buttery, golden topping with lightly crisp edges.
It is also flexible enough for a casual family dinner, a spring gathering, a church supper, or a holiday dessert table. Since the recipe makes about 12 servings, one pan can satisfy a crowd without needing individual desserts.
If you enjoy fruit-forward cakes with a little extra presentation, you may also like this rhubarb poke cake, which brings the same seasonal flavor in a different style.
Ingredients You’ll Need
The ingredient list is short, but each component has an important job. Use the following amounts for one 13 × 9-inch baking dish:
- 5 cups chopped rhubarb: Fresh rhubarb gives a bright, tangy flavor. Frozen rhubarb works too, but thaw and drain it first.
- 1 cup granulated sugar: This balances rhubarb’s natural tartness and helps create the bubbling fruit layer.
- One 3-ounce package strawberry gelatin mix: The gelatin provides strawberry flavor, sweetness, and a beautiful rosy tone.
- One 15–16 ounce package yellow cake mix: This becomes the tender, golden topping without requiring eggs or oil.
- 1 cup water: Water helps hydrate the dry cake mix as the dessert bakes.
- 1/2 cup unsalted butter, melted: Butter adds richness and helps the top brown while creating a delicate crispness.
Unsalted butter is preferred because the cake mix already contains seasoning, and it lets the fruit flavor remain clear. A standard yellow cake mix is the classic choice for this version, although the recipe’s layered method is what matters most.
For another easy dessert built around the same wonderfully simple baking approach, take a look at this pumpkin dump cake.
How to Make It Step-by-Step
Step 1: Heat the oven to 350°F (175°C), then grease a 13 × 9-inch baking dish with butter or nonstick cooking spray. Greasing helps with serving later, especially around the bubbling fruit edges.
Step 2: Spread the 5 cups of chopped rhubarb evenly over the bottom of the prepared dish. Try to create one level layer so the fruit cooks at a consistent rate from corner to corner.
Step 3: Sprinkle the granulated sugar evenly over the rhubarb, followed by the dry strawberry gelatin mix. Resist the temptation to stir, because the dessert depends on the separate layers releasing and combining naturally in the oven.
Step 4: Scatter the dry yellow cake mix over the top, covering the fruit as evenly as possible. Do not press the mix down or mix it with the rhubarb; a light, even layer gives the liquid room to travel through it.
Step 5: Pour the cup of water slowly over the cake mix, moving across the entire surface instead of pouring in one spot. Drizzle the melted butter in the same careful pattern, paying attention to the corners and edges where dry mix can otherwise remain.
Step 6: Place the dish in the 350°F oven and bake for 45–50 minutes. The cake is ready when the topping is golden brown and the rhubarb filling is visibly bubbling around the edges.
Step 7: Let the dump cake cool briefly before serving so the bubbling filling can settle slightly. Spoon it into bowls while warm and add vanilla ice cream or whipped cream for a classic finish.
Pro Tips for the Best Rhubarb Dump Cake
The dump cake technique is wonderfully forgiving, but even distribution makes a noticeable difference. Cake mix that stays dry in large pockets can leave powdery patches on top, so take an extra moment with the water and butter.
- Chop the rhubarb evenly: Pieces of similar size soften at roughly the same rate and make the filling easier to spoon.
- Drain frozen rhubarb: Thaw it completely and drain excess liquid before measuring or adding it to the dish. Extra moisture can make the finished dessert overly watery.
- Cover the surface carefully: Spread the cake mix from edge to edge, then pour the water and butter in thin, even streams.
- Never stir the layers: Mixing can disturb the balance of fruit, gelatin, dry mix, and liquid. The juices and added liquid are meant to soak through during baking.
- Watch the final minutes: Ovens vary, so begin checking near 45 minutes. Look for golden brown color and bubbling around the perimeter.
- Serve it warm: The contrast between hot rhubarb filling and cold vanilla ice cream makes this dessert especially appealing.
For a different fruit dessert with a tender crumb and plenty of homemade character, consider trying this banana Bundt cake next.
Serving Ideas and Occasion Pairings
A scoop of vanilla ice cream is the most familiar topping, and its cool creaminess melts into the warm strawberry-rhubarb filling. Whipped cream is another easy option, especially when you want a lighter finish.
For a little extra texture, add a few sliced strawberries or a small spoonful of plain yogurt. Keep additions simple so the tangy rhubarb and buttery cake topping remain the focus.
This recipe is especially welcome in spring when fresh rhubarb appears at farmers markets, but frozen rhubarb makes it practical all year. Serve it after a weeknight meal, bring it to a potluck, or bake it for a relaxed weekend gathering.
If apples are more your style, this Irish apple cake offers another cozy fruit dessert to add to your baking list.
Storage and Reheating
Allow leftovers to cool, then cover the baking dish and refrigerate them. The cake is best enjoyed within a few days, when the fruit remains flavorful and the topping still has some texture.
To reheat a serving, place it in a microwave-safe bowl and warm it in short intervals until heated through. You can also rewarm portions in an oven-safe dish, but watch carefully so the topping does not become too dark.
The topping may soften after refrigeration because it absorbs some of the fruit juices, but the dessert remains delicious. Add ice cream just before serving rather than storing it on top.
Rhubarb lovers may also want to save this strawberry rhubarb pie for a more traditional pastry-style dessert.
Easy Rhubarb Dump Cake Recipe for Any Occasion
Ingredients
Method
- Heat the oven to 350°F (175°C) and grease a 13 × 9-inch baking dish. Spread the chopped rhubarb evenly across the bottom.
- Sprinkle the sugar evenly over the rhubarb, then distribute the dry strawberry gelatin over the sugar. Do not stir the layers together.
- Sprinkle the dry yellow cake mix evenly over the fruit and gelatin. Pour the water across the surface, then drizzle the melted butter over the cake mix as evenly as possible.
- Bake for 45–50 minutes, until the top is golden brown and the rhubarb filling bubbles around the edges. Cool briefly before serving warm.
Notes
Final Thoughts
This easy rhubarb dump cake recipe proves that a memorable dessert does not require complicated techniques or a long ingredient list. Layer the ingredients without stirring, distribute the water and melted butter evenly, and let the oven transform them into a bubbling fruit dessert with a golden cake topping.
After 45–50 minutes, you will have a warm, comforting treat that serves about 12 people and fits nearly any occasion. Serve it with vanilla ice cream or whipped cream, and enjoy the sweet-tart flavor of rhubarb in one of the simplest desserts you can bake.