sweet potato rum cake
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Heirloom Sweet Potato Rum Cake

A lightly spiced, rum cake with a beautiful color, velvety texture, and delicate sweet potato flavor. Stores well at room temperature for at least a week. Store cake at room temperature for at least 24 hours before serving.
Prep Time 10 minutes
Cook Time 1 hour
Total Time 1 hour 10 minutes
Servings 24 servings



  • 2 1/2 cups all-purpose flour
  • 1 tablespoon baking powder
  • 1 teaspoon ground cinnamon
  • 1/2 teaspoon salt
  • 1 1/2 cups cooked sweet potato , mashed
  • 3 eggs
  • 3/4 cup Captain Morgan Spiced rum
  • 1 ¼ cups sugar
  • ½ cup light brown cane sugar
  • 1 cup melted unsalted butter
  • 1 teaspoon vanilla extract


  • 1/2 cup butter
  • 1/2 cup water
  • 3/4 cup granulated white sugar
  • 1 teaspoon Kosher salt
  • 3/4 cup Captain Morgan Spiced rum or Black Spiced rum



  • Preheat oven to 325 degrees F.
  • Lightly grease and flour a 10-cup bundt pan.
  • Mix the flour, baking powder, cinnamon, and salt in a large bowl.
  • Whisk the eggs, melted butter, vanilla, sugar, and brown sugar together.
  • Stir in the rum and sweet potatoes.
  • Stir in the dry ingredients.
  • Bake about an hour or until a toothpick inserted in the center comes out clean.


  • Combine the water, butter, sugar, and salt in a deep saucepan.
  • Cook over medium heat until the butter melts and the sugar dissolves.
  • Simmer it until it reduces just a little, about 2 more minutes.
  • Remove from the heat add the rum carefully.

To soak

  • Let the cake cool in the pan for ten minutes.
  • Remove it from the pan.
  • Now, put the cake right back in the pan (this will help it not to stick) and pour the rum syrup over it.
  • Pour the syrup slowly over the cake, cover, and let stand for at least 24 hours.
  • Invert onto a cake plate and serve.