Easy Blueberry Lemon Dump Cake
A super easy 6-ingredient dessert that comes together in just 10 minutes of prep. Juicy blueberries, bright lemon zest, and a golden buttery topping — all baked in one dish. Perfect with a scoop of vanilla ice cream!
Ingredients
- 4 cups fresh blueberries or frozen, thawed and drained
- ¼ cup granulated sugar adjust to taste
- 2 tbsp cornstarch
- 2 tbsp lemon zest divided — 1 tbsp for berries, 1 tbsp for topping
- 1 box yellow cake mix 13.25 oz, such as Betty Crocker Super Moist
- ½ cup unsalted butter (1 stick), sliced into ¼-inch pieces
Instructions
- Step 1 — Preheat & Prep the Pan Preheat your oven to 350°F (175°C). Lightly grease a 9×13 baking pan with butter or non-stick spray.Step 2 — Build the Blueberry Base Add the blueberries, granulated sugar, cornstarch, and 1 tablespoon of lemon zest directly into the prepared pan. Toss everything together until the berries are evenly coated, then spread the mixture into an even layer across the bottom.Step 3 — Add the Cake Mix Layer Pour the dry cake mix evenly over the blueberry layer, making sure to cover it completely from edge to edge. Sprinkle the remaining 1 tablespoon of lemon zest over the top of the cake mix, then gently work it in using your fingers or a spoon.Step 4 — Top with Butter Slice the butter into thin pieces, about ¼ inch thick, and arrange them in a single layer across the entire surface of the cake mix. Try to keep the pieces close together so the coverage is as even as possible.Step 5 — Bake Place the pan in the preheated oven and bake for 45–55 minutes, until the top is deep golden brown and the blueberry filling is bubbling up around the edges. Remove from the oven and allow to cool for 5–10 minutes before serving.Step 6 — Serve the scoop into bowls and top with a generous scoop of vanilla ice cream. Serve warm and enjoy!
Notes
- Berry swap: Raspberries, blackberries, or a mixed berry blend all work beautifully in place of or alongside the blueberries.
- Butter gaps: If you notice any dry, powdery spots of cake mix mid-bake, simply tuck in a small extra piece of butter and continue baking.
- Thicker cake: For a deeper, thicker dessert, use a smaller baking dish such as a 2.5–3 quart casserole dish and add 5–10 minutes to the bake time.
- Doneness preference: Pull the cake out early if you prefer a lighter, softer topping, or leave it in a few extra minutes for a deeper, crunchier golden crust.
- Storage: Store leftovers covered in the refrigerator for up to 4–5 days. Freeze for up to 3 months — wrap tightly in plastic wrap or foil before freezing. Thaw overnight in the fridge before reheating.
- Gluten-free option: Substitute a gluten-free yellow cake mix using a 1:1 ratio.