Moist, dense Sweet Potato Cake with Marshmallow Buttercream Frosting is a delicious twist on carrot cake. Perfect for fall, with warm spices, hints of sweet potato flavor, and decadent marshmallow cream frosting!
Years back, I attended a baking retreat hosted by Martha White with my buddy Brandie from The Country Cook. While there, we were tasked with creating a new recipe using Martha White’s sweet potato muffin mix. The end result was an AMAZING sweet potato cake with marshmallow buttercream Frosting. Sadly, it has become increasingly difficult to find that muffin mix, and I think it might actually be discontinued.
But never fear! I have come up with a solution. You see, I was thinking about fall recipes one day, specifically ones featuring sweet potatoes. And that recipe popped into my mind! So, I decided to come up with a new version of Sweet Potato Cake with Marshmallow Buttercream, and boy is it an improvement!
If you love sweet potatoes and the dense texture and warm spice flavor of carrot cake, you’re going to love this! It might just be my new favorite dessert. Pumpkin spice ain’t got nothing on this one! Y’all enjoy!
What is a sweet potato cake?
Sweet potato cake is something akin to a carrot cake but with sweet potatoes. I specifically took Heather’s Great Aunt Frankie’s Carrot Cake recipe, and I gave it a sweet potato twist.
Sweet potato cake is perfectly dense, amazingly moist, and not too crazy sweet, so the marshmallow buttercream is the perfect sweet topping. I mean, sweet potatoes and marshmallows go together perfectly, right?!
My sweet potato cake recipe has the perfect amount of sweet potato flavor without being overwhelming.
How to Store this Sweet Potato Cake
To store it properly, place the cake in an airtight container and refrigerate it for up to five days.
If you wish to freeze the cake, it’s best to do so soon after assembly. When you’re ready to enjoy it, thaw the cake overnight in the refrigerator and serve within 5 days for the best taste and texture.
Recipe FAQs
Will I really need that much shredded sweet potato? Yes, indeed! You’ll need about 3 cups to be exact. I just used a box grater to shred mine, but you can use a food processor as well. It took about 1 1/2 medium sweet potatoes to yield 3 cups. I suppose that one really large potato might give you enough also.
Should I use a metal, ceramic, or glass baking dish for this recipe? I like to bake this cake in a light-colored metal pan, but a ceramic or glass baking dish will work as well. Just keep in mind that using a different type of baking vessel may change the cook time. Dark-colored metal baking pans can often burn the outside of baked goods like this that require a lengthy time in the oven, so I might reduce the heat about 25° to help prevent that from happening.
Are pecans absolutely necessary in this recipe? While not absolutely necessary, I’d say they are highly encouraged. Yes, pecans can be a little pricey, but they’re worth it. Be sure to buy chopped pecans for this recipe. They’re cheaper to buy in pieces, and it saves you the step of having to chop them. You can also use walnuts, if you wish.
Recipe Card
Sweet Potato Cake with Marshmallow Buttercream
Ingredients
- 2 1/2 cups self-rising flour
- 1 teaspoon baking soda
- 1 1/2 teaspoons ground cinnamon
- 2 cups sugar
- 1 cup vegetable oil
- 4 large eggs
- 3 cups grated raw sweet potatoes (1 to 2 medium sweet potatoes)
- 1 1/2 cups chopped pecans
Buttercream Frosting
- 1 cup unsalted butter (room temperature)
- 2 (7-ounce) containers marshmallow cream
- 2 cups powdered sugar
- 1 pinch salt
Instructions
- Preheat the oven to 350°F and lightly spray a 9×13-inch baking pan with nonstick cooking spray. In a large bowl, whisk together the flour, baking soda, and cinnamon. Set aside.
- Use an electic mixer to beat together the sugar and oil until well combined. Add the eggs, one at a time, beating well after each addition. Add the flour mixture, all at once, and mix on low speed until well just combined. Scrape down the sides of the bowl, and mix again to ensure everything is combined. Fold in the sweet potatoes and pecans – reserving a few pecans to sprinkle on the top at the end.
- Pour the batter into the prepared pan. Bake for 50 to 60 minutes, or until a toothpick inserted in the center of the cake comes out clean. Cool completely.
For the frosting:
- Use an electric mixer to beat the butter until smooth. Add the marshmallow cream and mix until combined. Add the powdered sugar and a pinch of salt and mix until combined. Spread the buttercream on the cooled cake. Store the cake in the refrigerator.
Nutrition
* If nutritional values are provided, they are an estimate and will vary depending on the brands used. The values do not include optional ingredients or when ingredients are added to taste. If calorie count and other nutritional values are important to you, I recommend grabbing your favorite brands and plugging those ingredients into an online nutritional calculator.
Sheryl P
Love this cake! And so did my family! Making another one now!
Thanks, Sheryl! This one often gets overlooked, but I think it’s so good!
Alicyn Ferguson
Has this recipe been tried with all-purpose flour rather than self-raising? What is a good substitute?
Plain all-purpose won’t work without the addition of salt and baking powder. You can see how to turn all-purpose flour into self-rising flour here: https://southernbite.com/turn-all-purpose-flour-into-self-rising-flour/
Brandi
This looks amazing!! Quick question. I try avoid vegetable oil at all costs. Could I substitute an extra light olive oil or melted butter? Can’t wait to make this!!
Thank you!
Absolutely! Enjoy!
Joleen McCrimmon
Do you know if all purpose flour will work in this recipe?
Sure! You’ll just need to add the leavening to it. This will help: https://southernbite.com/turn-all-purpose-flour-into-self-rising-flour/
Lib M.
I made this as part of our Thanksgiving spread for two. I halved it and baked it in an 8″ by 8″ square pan. I started checking the time at 40 minutes, as I knew my half-recipe would be a slightly thinner cake and could require less cooking time. I think it was done in 47 minutes. The cake was fantastic. With only two of us, it lasted for several days, and maintained the moist texture. I will probably try baking it as muffins next time and see how freezing half of them works out. I ended up not frosting the cake. I thought the frosting was too sweet, and that the cake didn’t need it. I think my sweet tooth is decreasing as I age… That cake though – delicious! The flavor and texture reminded me of my grandmother’s apple cake.
So glad to hear you enjoyed it, Lib!
ELIZABETH W.
Stacey, this looks and sounds delicious! I might have to reduce the amount of sweet potato and add some crushed pineapple, though…I love pineapple with my sweet ‘taters and in my carrot cake. lol
Thanks for sharing all these wonderful recipes!
That sounds great! You are so welcome!
Carol
What could a low sugar substitute be for the sweet marshmallow frosting?
Gosh, I just don’t know. I’m going to have to think on that one.
ELIZABETH
Carol. it won’t have the same flavor as the yummy marshmallow buttercream, but you might try combining softened cream cheese with whipped cream, vanilla, and sugar replacer of your choice…or with some Cool Whip.
I usually just use Cool whip, because it’s more stable than fresh whipped cream.
Just whip the cream cheese with about 1/3 cup Splenda or Swerve and 1/2 Tbsp molasses (or honey) until it’s soft and creamy, the fold in about 4 cups of Cool Whip. It’s a a great alternative to traditional powdered sugar based frostings.
This is such a GREAT idea! And I agree, Cool Whip does work better in stuff like this. And don’t they make sugar free Cool Whip?
Maggie Sewell
can this be made into a loaf bread
I’ve not tried that, so I can’t say for sure.
Phyl
Stacy, I made the cake and it was delicious. I thought I had marshmallow creme but no I didn’t, so I had to make the old fashioned cream cheese icing. I will be making this again with the yummy frosting! Thanks Stacy so much for your great recipes!!!
I’m so glad that you enjoyed it!
Kathleen Pope
This looks so amazing and I love the sweet potato twist and that frosting!
Thank you, Kathleen!!
Claudine
Stacey,
I got ready to make this cake and I need a quick clarification on an ingredient please. The cake calls for grated sweet potatoes. Do you grate the potatoes and add them raw to the cake batter or do you cook the potatoes, grate them and then add them to the cake batter? Thank you.
Claudine in Fort Worth, TX
They are raw when they go into the batter. Hope that helps. Let me know if I can help in any other way.
Claudine
Now, this cake will surely be on my list for Thanksgiving. I love sweet potato pie, but my pie crusts, well lets just say they turn out like frisbees instead of pie crusts. No matter what I do or how I do it, they are terrible unless I buy frozen crusts. LOL! So I say, this will definitely be on the Thanksgiving dessert table for sure.
Thanks Stacey for sharing.
Claudine in Fort Worth, TX
I’m not great at crusts either! They can be quite finicky. Hopefully, this cake will be much easier!
Phyl
Great looking cake. Did you use Martha White flour? It looks fluffy instead of packed inside like some flours do!
No, for this one I just used the store brand of self-rising flour.
Nancy Tobin
Love all your recipes..!
Making the pineapple juice cake next.
Your recipes so through and Thanks so much!
I do have a question: Could i use less sugar in the
sweet potato cake. Like half the recipe?
Just a thought. Again, THANKS! nancyt 🙂
Thanks so much, Nancy! I sure hope you’ll enjoy the Pineapple Juice Cake. It sure is a favorite of mine! In this cake you can certainly use less sugar. I’m not sure I’d cut it by half, but it’s totally up to you. I will say, the frosting is pretty sweet, so if you’re looking to cut back on sugar, you could always cut the entire frosting recipe in half.