Easy Apple Rhubarb Dump Cake (Only 4 Ingredients!)
This Apple Rhubarb Dump Cake is a fuss-free, 4-ingredient dessert that turns frozen or fresh rhubarb and tender apples into a golden, bubbly cake with almost zero effort.
The Easiest Apple Rhubarb Cake You Will Ever Make
If you have ever stood in your garden staring at a mountain of rhubarb stalks wondering what on earth to do with them, this recipe is about to become your new best friend. This Apple Rhubarb Dump Cake is one of those rare 4 ingredient recipes dessert lovers go absolutely wild for because it tastes like you spent hours in the kitchen, but it comes together in about 10 minutes of actual effort.
The tart, jammy rhubarb softens beneath a layer of sweet apple pie filling, the marshmallows melt into a gooey, caramelized ribbon in the middle, and a golden, buttery cake crust forms right on top as it bakes. It is warm, bubbling, and absolutely perfect served with a big scoop of vanilla ice cream.
Getting the right pantry staples makes all the difference here. A good quality canned apple pie filling with real apple pieces and a reliable yellow cake mix are the backbone of this recipe, and they are worth picking thoughtfully.
Why This Recipe Works So Well
Dump cake recipes are easy by design, but this particular combination is genuinely special. Rhubarb is naturally very tart, and that tartness plays perfectly against the sweetness of the apple pie filling and cake mix. You get complexity and balance without any real technique.
This recipe also solves the eternal question of what to do with a glut of rhubarb. Recipes using frozen rhubarb work just as well here as fresh, which means you can freeze your garden harvest in the summer and pull this together on a cold February night. Canned rhubarb recipes work too if that is what you have on hand.
Chef's Tip: Do not skip the mini marshmallows if you can help it. They dissolve into the fruit layer and create a soft, almost jammy interior that takes this from a simple dump cake to something that tastes like a rhubarb marshmallow cake. It is a small addition with a big payoff.
Fresh, Frozen, or Canned: Which Rhubarb Should You Use?
All three work beautifully in this recipe, and that flexibility is part of what makes it such a practical keeper.
- Fresh rhubarb gives the brightest, most vibrant flavor. Chop it into half-inch pieces and layer it straight into the dish.
- Frozen rhubarb is ideal for year-round baking. No need to thaw it first. The bake time may run slightly longer, but the result is just as delicious.
- Canned rhubarb should be drained before using to avoid a watery filling.
If you have been searching for apple rhubarb cake recipes that do not require a mixer, a double boiler, or any baking intuition at all, you have officially found your recipe.
Tips for the Best Rhubarb Dump Cake
A few small details make a real difference in the final result:
- Cover the cake mix fully with butter pats. Any dry spots on top will not bake through properly and can taste powdery. Thin, even slices of cold butter spread across the whole surface are key.
- Do not stir. The layers need to stay separate so the butter can do its job as it melts down through the dry mix.
- Let it rest. Giving the cake 10 minutes out of the oven lets the filling thicken up slightly and makes scooping much cleaner.
- For a rhubarb cake with cake mix recipe that skews more tart, add a squeeze of fresh lemon juice over the rhubarb before layering on the apple filling.
Ready to make this gorgeous, bubbly dessert? Here is everything you need:
Easy Apple Rhubarb Dump Cake (Only 4 Ingredients!)
This Apple Rhubarb Dump Cake is a fuss-free, 4-ingredient dessert that turns frozen or fresh rhubarb and tender apples into a golden, bubbly cake with almost zero effort.
Ingredients
- 3 cups rhubarb, fresh, frozen, or canned and drained; cut into 0.5-inch pieces if fresh
- 21 oz apple pie filling, one standard can
- 2 cups mini marshmallows, optional but adds a gooey, caramelized layer
- 15 1/4 oz yellow cake mix, one standard box, dry and unprepared
- 1/2 cups unsalted butter, thinly sliced into pats
Instruction
Preheat your oven to 350 degrees F (175 degrees C). Lightly grease a 9x13-inch baking dish with butter or nonstick spray.
Spread the rhubarb pieces evenly across the bottom of the prepared baking dish.
Spoon the apple pie filling evenly over the rhubarb layer, spreading it gently to cover.
Scatter the mini marshmallows over the apple layer if using. They will melt into the fruit and create a wonderfully gooey, lightly caramelized middle.
Sprinkle the dry cake mix straight from the box over the entire fruit layer, distributing it as evenly as possible. Do not stir.
Lay the thin pats of butter evenly across the top of the dry cake mix, covering as much of the surface as you can. The butter melts down through the mix as it bakes, creating a golden, crisp topping.
Bake uncovered for 45 to 55 minutes, until the top is golden brown and the fruit filling is bubbling around the edges.
Remove from the oven and let the cake rest for at least 10 minutes before serving. Scoop and serve warm with a scoop of vanilla ice cream or a dollop of whipped cream.
Equipment
- 9x13-inch baking dish
- Nonstick cooking spray or butter for greasing
- Cutting board and knife (if using fresh rhubarb)
- Spatula or spoon for spreading
Notes
Serving and Storing Your Apple Rhubarb Dump Cake
This cake is at its very best served warm, straight from the baking dish. A generous scoop of vanilla bean ice cream is the classic pairing, but freshly whipped cream or even a drizzle of heavy cream works beautifully too.
Leftovers keep covered in the refrigerator for up to 4 days and reheat quickly in the microwave. The cake also freezes well for up to 2 months, making it a fantastic make-ahead dessert for holidays or gatherings.
Whether you are working through a rhubarb harvest, browsing canned rhubarb recipes, or just craving one of those effortless dump cake recipes that delivers every single time, this apple rhubarb version is one you will return to again and again.
