01 -
Preheat the oven to 350°F (175°C) and prepare a 9x13-inch baking pan by greasing and flouring.
02 -
In a large bowl, mix the mashed sweet potatoes, granulated sugar, brown sugar, oil, eggs, buttermilk, and vanilla extract until smooth.
03 -
In a separate bowl, sift together the flour, baking powder, baking soda, salt, cinnamon, nutmeg, and ginger.
04 -
Gradually blend the dry ingredients into the wet mixture, stirring until well combined.
05 -
In a small bowl, mix the sugar and cinnamon for the cinnamon swirl.
06 -
Pour half of the cake batter into the prepared baking pan, then sprinkle half of the cinnamon swirl mixture over it.
07 -
Add the remaining batter and gently swirl with a knife, then sprinkle the remaining cinnamon swirl mixture on top.
08 -
Bake for 35-40 minutes, or until a toothpick inserted in the center comes out clean.
09 -
Let the cake cool completely in the pan on a wire rack.
10 -
For the glaze, whisk together the powdered sugar, milk, and vanilla extract. Drizzle over the cooled cake.