Rhubarb Dump Cake
When I think of comfort food, the first dish that comes to mind is Rhubarb Dump Cake. There’s something so nostalgic and inviting about the combination of tart rhubarb and a sweet, buttery cake topping. Growing up, my grandmother made this dish for family gatherings, filling the house with an irresistible aroma that drew everyone into the kitchen. It was a true centerpiece of our spring celebrations, especially when rhubarb was in season. This cake is not only easy to make, but it also captures the essence of warm memories spent with loved ones around the table.
Recipe Snapshot
50 mins
5 mins
45 mins
Medium
320 kcal
3 g
Gluten-Free, Low FODMAP
14 g
Cutting Board, Frying Pan, Wooden Spoon, Oven, Mixing Bowl, Baking Sheet
What Sets This Rhubarb Dump Cake Apart
Quick and Simple Preparation
One of the reasons I adore Rhubarb Dump Cake is its simplicity. You don’t need to be a baking expert to whip this up. Just mix the ingredients, pour them into a pan, and let the oven do the work. It’s the perfect dessert for those busy weeknights when you want something sweet without spending hours in the kitchen.
Bold Flavor Combinations
The pairing of tart rhubarb with sweet sugar and buttery cake creates an incredible flavor profile. Each bite offers a delightful contrast that keeps you coming back for more. I love how this cake balances sweetness and tartness, making it a crowd-pleaser at any gathering.
Perfect for Any Occasion
This dish isn’t just reserved for spring; it can brighten up any gathering year-round. Whether it’s a picnic, potluck, or simply a cozy evening at home, Rhubarb Dump Cake fits in perfectly. It’s a dessert that evokes warmth and comfort, making it an ideal ending to any meal.
Versatile Ingredient Options
You can easily adapt this recipe based on what you have at home. For instance, if you don’t have rhubarb, you can substitute it with other fruits like strawberries or blueberries. This versatility means you can enjoy a delicious dessert regardless of the season or the ingredients on hand.
Easy Clean-Up
With Rhubarb Dump Cake, clean-up is a breeze. Since the ingredients are mixed in one bowl and poured directly into the baking dish, you won’t find yourself facing a mountain of dishes afterward. This makes it a practical choice for those who want to enjoy delightful desserts without the hassle of extensive clean-up.
Ideal for Sharing and Enjoying
This cake is perfect for sharing with friends and family. Its generous portion size means that it can easily serve a crowd, allowing everyone to enjoy a slice (or two!). There’s something special about sharing food made from the heart, and this cake is no exception.
What You Need for Rhubarb Dump Cake

Gathering the ingredients for Rhubarb Dump Cake is part of the fun! Each component plays a vital role in building flavor and texture. The rhubarb is the star of the show, bringing that signature tartness, while the sugar balances it out perfectly. The yellow cake mix adds a delightful sweetness and a fluffy texture, making it a wonderful base for this delicious dessert.
- 4 cups fresh rhubarb (1 to 1¼ pounds, small diced): The main ingredient that provides tartness and texture.
- 1½ cups granulated sugar: This balances the tartness of the rhubarb and adds sweetness.
- 2 tablespoons cornstarch: Helps thicken the filling, creating a luscious texture.
- 1 teaspoon vanilla extract: Adds depth and warmth to the overall flavor.
- 1 cup water (divided): Necessary for the cake’s moisture and consistency.
- 15.25 ounces yellow cake mix (super moist): A quick and easy base that creates a light, fluffy topping.
- 1 cup unsalted butter, melted: Provides richness and helps brown the cake mix.
Step by Step Instructions for Rhubarb Dump Cake

Making Rhubarb Dump Cake is as easy as 1-2-3! Follow these simple steps to create a delicious dessert that everyone will love. You’ll be amazed at how quickly this comes together!
Preheat the oven to 375°F. This initial step is crucial as it ensures your cake bakes evenly. Make sure your oven is at the right temperature before you start.
Spray a 9Ă—13 pan with baking spray. This prevents the cake from sticking to the pan and makes serving so much easier later on.
Combine the diced rhubarb, sugar, ½ cup water, cornstarch, and vanilla extract in a large bowl. Stir to combine evenly. This mixture will create a delicious filling for your cake, so make sure all the ingredients are well blended.
Pour the mixture into your prepared pan. Spread it out evenly so that every slice has a good balance of filling.
Evenly sprinkle the boxed yellow cake mix over the top of the rhubarb mixture. If needed, you can spread the cake mix to ensure that all the fruit is covered in an even layer. This helps to create a moist, flavorful topping that complements the filling.
Drizzle the remaining ½ cup of water evenly over the layer of yellow cake mix. This step is key to ensuring that the cake mix hydrates properly during baking.
Carefully drizzle the melted butter evenly over the water and yellow cake mix. This will help the topping become golden and crispy.
Bake for 45 minutes or until golden and bubbly. Keep an eye on it as it bakes; the top should turn a lovely golden brown and the filling should be bubbling.
Remove the rhubarb dump cake from the oven and allow it to rest on the counter for 15 minutes before serving. This resting time enhances the flavor and allows the cake to set, making it easier to cut into squares.
Things Worth Knowing
- Choosing Rhubarb: When selecting rhubarb, look for firm, vibrant stalks. Avoid any that are wilted or have blemishes, as they may not be as flavorful.
- Thickness of the Cake: For a thinner cake, use a larger pan. A 9Ă—13-inch pan is ideal for achieving that perfect balance of filling and topping.
- Checking for Doneness: The cake should be bubbly and golden brown when it’s done. If you notice it browning too quickly, cover it lightly with aluminum foil.
- Storage Tips: Store leftovers in an airtight container in the fridge for up to three days. Reheat in the oven for the best texture.
- Serving Suggestions: This cake pairs beautifully with whipped cream or vanilla ice cream for an extra indulgent treat.
Helpful Hints

Here are some helpful hints to ensure your Rhubarb Dump Cake turns out perfectly every time!
- Storage: Leftover cake should be stored in an airtight container in the fridge, and it’s usually best consumed within three days for optimal taste.
- Freezing: You can freeze the cake for up to two months. Just make sure to wrap it tightly in plastic wrap before placing it in a freezer-safe container.
- Pairing: This cake goes wonderfully with a scoop of vanilla ice cream or a dollop of whipped cream to balance the tartness of the rhubarb.
- Ingredient Substitution: If you want to experiment, you can replace rhubarb with other fruits like strawberries or peaches, keeping the same method.
- Watch the Baking Time: Every oven is different. Make sure to check your cake a few minutes before the suggested baking time ends to prevent over-baking.
- Serving Warm: Serving it warm enhances the flavors, making it an even more delightful treat.
- Oven Calibration: If you’re not sure your oven’s accurate, it’s a good idea to double-check with an oven thermometer, especially for baked goods.
Serving Ideas for Rhubarb Dump Cake
When it comes to serving Rhubarb Dump Cake, the possibilities are endless! Here are some delicious ideas to elevate your dessert experience:
- Whipped Cream: A generous dollop of whipped cream adds a light, airy touch to the tart cake.
- Vanilla Ice Cream: Pairing this cake with a scoop of creamy vanilla ice cream creates a delightful contrast of temperatures and textures.
- Fresh Berries: Fresh strawberries or blueberries sprinkled on top add a pop of color and enhance the fruity flavor.
- Tea or Coffee: Serve slices of this cake alongside a warm cup of tea or coffee for a cozy afternoon treat.
- Picnic Treat: Perfect for outdoor gatherings, Rhubarb Dump Cake is easy to transport and share among friends.
- Spring Celebrations: This cake is an ideal dessert for springtime events, family reunions, or holiday brunches.
- Leftover Breakfast: Enjoy a slice for breakfast the next day with your morning coffee for a sweet start!
FAQ
Conclusion
The Rhubarb Dump Cake is a fantastic dessert that beautifully blends sweet and tart flavors while being incredibly easy to prepare. It’s a perfect choice for any gathering, offering comfort and nostalgia in every bite. I encourage you to try making this delightful cake for your next family event or cozy evening at home. You won’t regret savoring each delicious slice!

Rhubarb Dump Cake
Ingredients
Equipment
Method
- Preheat the oven to 375°F. This initial step is crucial as it ensures your cake bakes evenly. Make sure your oven is at the right temperature before you start.
- Spray a 9Ă—13 pan with baking spray. This prevents the cake from sticking to the pan and makes serving so much easier later on.
- Combine the diced rhubarb, sugar, ½ cup water, cornstarch, and vanilla extract in a large bowl. Stir to combine evenly. This mixture will create a delicious filling for your cake, so make sure all the ingredients are well blended.
- Pour the mixture into your prepared pan. Spread it out evenly so that every slice has a good balance of filling.
- Evenly sprinkle the boxed yellow cake mix over the top of the rhubarb mixture. If needed, you can spread the cake mix to ensure that all the fruit is covered in an even layer. This helps to create a moist, flavorful topping that complements the filling.
- Drizzle the remaining ½ cup of water evenly over the layer of yellow cake mix. This step is key to ensuring that the cake mix hydrates properly during baking.
- Carefully drizzle the melted butter evenly over the water and yellow cake mix. This will help the topping become golden and crispy.
- Bake for 45 minutes or until golden and bubbly. Keep an eye on it as it bakes; the top should turn a lovely golden brown and the filling should be bubbling.
- Remove the rhubarb dump cake from the oven and allow it to rest on the counter for 15 minutes before serving. This resting time enhances the flavor and allows the cake to set, making it easier to cut into squares.


