Sweet Potato Dump Cake

The melted butter doesn’t vanish into the yellow cake mix the moment it lands; pale patches can stay dry if the drizzle misses a spot. I take a slow pass over the whole surface rather than pouring the butter in one place. That small bit of attention helps this Sweet Potato Dump Cake bake into a golden top instead of a topping with floury pockets.

Underneath, canned sweet potatoes, eggs, and evaporated milk make a smooth, softly set layer with cinnamon and nutmeg. Keeping that mixture separate from the dry cake mix gives the dessert its defining contrast: a tender sweet potato base and a buttery cake topping.

The pecans toast on top while the layers bake together, and a short rest gives the center time to settle before serving. Each spoonful brings a little crunch, warm spice, and a soft, custardy bite.

Why the Sweet Potato Layer Needs to Stay Under the Cake Mix

It can look odd to spread a wet filling in the pan and leave a blanket of dry cake mix on top, but that separation is what gives this dessert its two distinct textures. The sweet potato mixture bakes into a soft, custard-like base. Above it, the cake mix and melted butter form a golden topping with a more crumbly, cake-like bite.

Stirring everything together would change the balance: the cake mix would no longer sit in a separate layer, and the top couldn’t brown the same way. The butter also needs to reach across the surface rather than collect in a few shiny pools. Think of the topping as a layer to cover, not batter to mix. When the cake comes out, look for a golden top and no visible patches of dry mix; the center of the sweet potato layer provides the more dependable doneness check.

This is a richer, softer dessert than a sliceable layer cake, so expect the first serving to be spooned rather than cut into perfect squares. After resting, the base holds together better while still staying tender.

What Each Layer Brings to Sweet Potato Dump Cake

• Canned sweet potatoes or yams — Either works here, and a store brand is fine. Drain them well before mashing; extra canning liquid would thin the base. Choose whichever one you prefer, knowing yams often taste a little sweeter.
• Eggs and evaporated milk — Together, they give the sweet potato layer its structure and creamy texture. Evaporated milk is unsweetened and concentrated, not the same as sweetened condensed milk; regular milk would make a looser mixture.
• Cinnamon, nutmeg, vanilla, and sugar — These season the base without overpowering the sweet potatoes. Fresh, fragrant spices make the most difference, but ordinary pantry spices work well; there’s no need for a specialty brand.
• Yellow cake mix — Use it dry, straight from the box. It supplies the topping’s cake-like texture without needing a separate batter, and a standard grocery-store mix is all you need.
• Unsalted butter and pecans — Unsalted butter lets the measured salt in the base do its job without making the whole dessert taste too salty. Fresh pecans add crunch; if yours smell stale or bitter, leave them out rather than using them.

Layering and Baking for a Golden, Set Top

Whisk the sweet potato base until smooth

Heat the oven to 350°F and grease a 9×13-inch baking dish. In a large bowl, whisk the mashed sweet potatoes with the eggs, evaporated milk, sugar, vanilla, cinnamon, nutmeg, and salt. Keep whisking until the mixture looks even, with no obvious streaks of egg or large lumps of sweet potato. Spread it across the prepared dish in a level layer.

Keep the dry topping in its own layer

Sprinkle the yellow cake mix evenly over the sweet potato mixture without stirring it in. Scatter the chopped pecans over the cake mix so they’re spread across the surface rather than gathered in the middle. Drizzle the melted butter over the entire top; a slow, even pour helps avoid isolated dry patches. Don’t prepare the cake mix as batter first.

Bake until the top is golden and the center is set

Bake for 55 to 70 minutes. The top should turn golden, and there shouldn’t be visible dry cake mix remaining. Check the center of the sweet potato layer with a food thermometer; it should reach 160°F. If the top looks ready before the center reaches that temperature, keep baking and check again.

Let the cake settle before serving

Take the dish from the oven and leave it to rest before serving. The hot filling is soft right out of the oven, so cutting or scooping immediately can make it spread across the dish. Once it has had time to settle, serve portions with some of the pecan topping in each scoop.

Two Simple Ways to Adapt the Topping and Base

Questions That Come Up Before the First Bite

Sweet Potato Dump Cake

Sweet potato dump cake layers a smooth, cinnamon-spiced sweet potato filling with yellow cake mix, pecans, and melted butter. Bake it until the topping is golden and the center reaches 160°F, then rest for 20 minutes before serving.

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Prep Time 15 minutes mins

Cook Time 1 hour hr 10 minutes mins

resting 20 minutes mins

Total Time 1 hour hr 45 minutes mins

Servings: 12 servings

Course: Dessert

Cuisine: American

Calories: 480

Ingredients Equipment Method Notes

Ingredients

  

For the sweet potato layer

• 2 can (29 oz) sweet potatoes or yams drained and mashed
• 2 eggs large
• 1 can (12 oz) evaporated milk
• 0.5 cup granulated sugar
• 1 tsp vanilla extract
• 1 tsp ground cinnamon
• 0.25 tsp ground nutmeg
• 0.25 tsp kosher salt

For the topping

• 1 box (15.25 oz) yellow cake mix
• 1 cup unsalted butter melted
• 1 cup pecans chopped

Equipment

• 1 9x13-inch baking dish

Method

 

Prepare the sweet potato layer

1. Heat the oven to 350°F.
2. Grease a 9x13-inch baking dish.
3. In a large bowl, whisk together the mashed sweet potatoes, eggs, evaporated milk, granulated sugar, vanilla extract, ground cinnamon, ground nutmeg, and kosher salt until smooth.
4. Spread the sweet potato mixture in the baking dish.

Add the topping and bake

1. Sprinkle the dry yellow cake mix evenly over the sweet potato layer.
2. Scatter the chopped pecans over the cake mix.
3. Drizzle the melted unsalted butter evenly over the top.
4. Bake for 55 to 70 minutes, until the topping is golden with no dry cake mix visible and the center of the sweet potato layer reaches 160°F.
5. Rest the cake for 20 minutes before serving.

Notes

For an even topping, spread the dry cake mix all the way to the edges before adding the pecans and butter. Refrigerate leftovers for up to 4 days; freezing is suitable. For a gluten-free option, use a gluten-free yellow cake mix.