Name: Grandma's Famous Sweet Potato Butter Cake
Prep time: 15 min
Cook time: PT-485761H55M33S
Total time: PT-485761H55M33S
Cuisine: American
Ingredients: 1 cup (2 sticks) unsalted butter, softened; 1½ cups granulated sugar; 4 large eggs; 1 cup mashed sweet potatoes (about 1 large cooked and peeled sweet potato); ½ cup sour cream (room temperature); ¼ cup milk (whole or 2%); 2 teaspoons vanilla extract; 2 cups all-purpose flour; 2 teaspoons baking powder; ½ teaspoon baking soda; ½ teaspoon salt; 1 teaspoon ground cinnamon; ¼ teaspoon ground nutmeg; Optional Glaze:; 4 tablespoons (½ stick) unsalted butter, melted; ½ cup powdered sugar; 1–2 tablespoons milk; ½ teaspoon vanilla extract

A slice of rich, moist sweet potato butter cake that carries the warmth of cinnamon and nutmeg in every bite. This heirloom recipe transforms humble sweet potatoes into a decadent dessert that’s perfect for family gatherings, holiday celebrations, or simply satisfying your sweet tooth on a cozy afternoon.

Why You’ll Love This Recipe

This Sweet Potato Butter Cake is the perfect balance of comforting and indulgent. The natural sweetness of sweet potatoes blends beautifully with butter and warm spices to create a moist, tender cake that’s impossible to resist. It’s sophisticated enough for special occasions yet simple enough for everyday baking. The optional glaze adds a touch of sweetness that complements the subtle spice notes. Best of all, this recipe transforms nutritious sweet potatoes into a dessert that will have everyone asking for seconds!

Ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)

All-purpose flour forms the foundation of this cake, providing structure while still allowing for a tender crumb. Make sure to measure it correctly by spooning it into your measuring cup and leveling off the top.
Granulated sugar sweetens the cake while also helping to create that perfect tender texture as it incorporates with the butter during creaming.
Unsalted butter is essential for that rich, melt-in-your-mouth quality that makes this cake special. Using unsalted allows you to control the salt content, but if you only have salted butter, simply reduce the added salt in the recipe.
Eggs bind the ingredients together and provide structure and richness. Let them come to room temperature for the best incorporation into the batter.
Sweet potatoes are the star of this show, bringing natural sweetness, gorgeous color, and moisture to the cake. For the best flavor and texture, roast your sweet potatoes rather than boiling them – this concentrates their flavor.
Sour cream adds incredible moisture and a subtle tanginess that balances the sweetness. If you don’t have sour cream, full-fat Greek yogurt makes an excellent substitute.
Milk helps thin the batter to the perfect consistency while adding additional moisture. Whole milk works best, but 2% will also work fine.
Vanilla extract enhances all the other flavors in the cake with its warm, aromatic notes.
Baking powder and baking soda work together as leavening agents to give the cake its perfect rise.
Salt enhances all the flavors and balances the sweetness. Don’t skip it, even in sweet baked goods!
Cinnamon and nutmeg provide that classic warm, spiced flavor that pairs perfectly with sweet potatoes. Feel free to adjust to your taste or add other spices like ginger or cloves.
Powdered sugar creates a smooth, sweet glaze that adds the perfect finishing touch to the cake.

Directions

Preheat your oven to 350°F (175°C). Thoroughly grease and flour either a 9×13-inch baking dish or a bundt pan, ensuring you get into all the crevices.
In a large mixing bowl, beat the softened butter and granulated sugar together until the mixture becomes light and fluffy, about 2–3 minutes. Remember to scrape down the sides of the bowl occasionally for even mixing.
Add the eggs one at a time, mixing well after each addition to ensure proper incorporation.
Stir in the mashed sweet potatoes, sour cream, milk, and vanilla extract, mixing until the batter is smooth and uniform.
In a separate bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon, and nutmeg until well combined.
Gradually add the dry ingredients to the wet ingredients, stirring gently until just combined. Be careful not to overmix, as this can result in a tough cake.
Pour the batter into your prepared pan and smooth the top with a spatula to ensure even baking.
Bake according to your pan choice:
- 9×13-inch pan: 40–45 minutes
- Bundt pan: 50–60 minutes
The cake is done when a toothpick inserted in the center comes out clean or with just a few moist crumbs.
Allow the cake to cool in the pan for 15 minutes before transferring to a wire rack to cool completely.
For the optional glaze, melt butter in a small saucepan. Whisk in powdered sugar, milk, and vanilla extract until smooth. Adjust consistency as needed by adding more milk or powdered sugar. Drizzle the glaze over the cooled cake.
Slice and serve, savoring each delicious bite!

Servings and Timing

This Sweet Potato Butter Cake serves 12-15 people when baked in a 9×13-inch pan or 8-10 people when using a bundt pan. Each serving contains approximately 320 calories.

Preparation Time: 15 minutes
Cooking Time: 45-60 minutes (depending on pan choice)
Total Time: 1 hour to 1 hour 15 minutes

Variations

Spice It Up: Add 1/4 teaspoon of ground ginger, a pinch of cloves, or 1/2 teaspoon of pumpkin pie spice for more complex flavor.
Nutty Delight: Fold in 1/2 cup of chopped pecans or walnuts to the batter for added texture and flavor.
Cream Cheese Frosting: Replace the glaze with a classic cream cheese frosting for a richer dessert experience.
Sweet Potato Streusel Cake: Create a streusel topping with 1/2 cup brown sugar, 1/4 cup flour, 3 tablespoons cold butter, and 1/2 cup chopped nuts. Sprinkle over the batter before baking.
Chocolate Chip Version: Add 1 cup of semi-sweet chocolate chips to the batter for a delightful sweet potato chocolate chip cake.
Maple Glaze: Substitute maple syrup for the milk in the glaze for a seasonal flavor twist.
Mini Cakes: Bake in muffin tins for about 18-20 minutes to create individual serving-sized cakes.

Storage/Reheating

Counter Storage: Store the unfrosted cake in an airtight container at room temperature for up to 3 days. If glazed, the cake may need refrigeration after 1-2 days.
Refrigerator Storage: For longer freshness, store the cake in the refrigerator for up to 1 week. Place in an airtight container to prevent it from absorbing other flavors.
Freezer Storage: This cake freezes beautifully for up to 3 months. Wrap individual slices or the entire unfrosted cake tightly in plastic wrap, then aluminum foil or in a freezer-safe container. Thaw overnight in the refrigerator before serving.
Reheating: For that fresh-baked taste, reheat individual slices in the microwave for 10-15 seconds. You can also warm slices in a 300°F oven for about 5-7 minutes.
Glaze Later: If planning to freeze, it’s best to freeze the cake unglazed and add fresh glaze after thawing.

FAQs

Can I use canned sweet potatoes instead of fresh?

Yes, you can use canned sweet potatoes, but drain them well and mash thoroughly. Fresh sweet potatoes typically provide better flavor, but canned can be a time-saving alternative. Just make sure they’re plain sweet potatoes without added syrup or spices.

How do I prepare the sweet potatoes for this recipe?

The best method is to bake whole sweet potatoes at 400°F for about 45-60 minutes until fork-tender. Let them cool, then peel and mash. You can also microwave them for about 8-10 minutes, turning halfway through. Avoid boiling as it can make them too watery.

Can I make this cake ahead of time?

Absolutely! This cake actually tastes even better the day after baking as the flavors have time to meld. You can make it 1-2 days in advance and store it covered at room temperature, or bake it up to 3 months ahead and freeze it unglazed.

Is this cake good without the glaze?

Yes! While the glaze adds a nice touch of sweetness, the cake is delicious on its own. The natural sweetness of the sweet potatoes and the richness from the butter and sour cream make it perfectly enjoyable unglazed.

Can I substitute pumpkin for sweet potatoes?

Yes, you can substitute an equal amount of pumpkin puree for the mashed sweet potatoes. The flavor will be slightly different but still delicious. Make sure to use plain pumpkin puree, not pumpkin pie filling.

Why is my cake dry?

Dry cake usually results from overbaking or measuring flour incorrectly. Make sure to spoon flour into measuring cups rather than scooping, and check your cake with a toothpick 5 minutes before the minimum baking time.

Can I make this recipe gluten-free?

Yes, you can substitute a 1:1 gluten-free baking flour blend for the all-purpose flour. The texture may be slightly different, but the cake will still be delicious.

Can I reduce the sugar in this recipe?

You can reduce the sugar by up to 1/4 cup without significantly affecting the texture. The sweet potatoes add natural sweetness, so the cake will still taste good with less added sugar.

What can I substitute for sour cream?

Greek yogurt, buttermilk, or even full-fat plain yogurt can replace sour cream. Each will contribute slightly different flavors and textures, but all work well in this recipe.

Can I make this into cupcakes?

Absolutely! Fill cupcake liners about 2/3 full and bake at the same temperature for approximately 18-22 minutes. This recipe should yield about 24 cupcakes.

Conclusion

Grandma’s Famous Sweet Potato Butter Cake is more than just a dessert – it’s a slice of comfort and tradition that brings people together. The natural sweetness of sweet potatoes paired with warm spices creates a cake that’s moist, flavorful, and impossible to resist. Whether you’re serving it at a holiday gathering, bringing it to a potluck, or simply enjoying it with your afternoon coffee, this cake is sure to become a treasured recipe in your collection. Its versatility allows for countless variations while the straightforward preparation makes it accessible for bakers of all skill levels. Give this sweet potato butter cake a try – it might just become your family’s new favorite tradition!

Grandma’s Famous Sweet Potato Butter Cake