Step 1

Preheat oven to 350 degrees F. Grease and flour or line with parchment paper, an 8" square or round pan. Set aside.

Step 2

In a large mixing bowl, whisk together flour, sugar, baking soda, baking powder and salt.

Step 3

Add egg, buttermilk, vanilla and oil. Whisk together. Add hot water and whisk well until the batter is smooth. It will be runny but that's okay.

Step 4

Pour batter into prepared pan. Tap the pan gently against the counter to release any air bubbles.

Step 5

Bake cake for 25 to 28 minutes or until golden on top and a toothpick inserted in a few places comes out clean.

Step 6

Cool cake completely before frosting.

Step 7

To make frosting: place butter in a medium mixing bowl and beat for 7 minutes. Add powdered sugar, 1/2 cup at a time and beat in well. Add heavy cream and beat in for 1 minute. Add vanilla and mix in. The frosting should be very fluffy. Spread over cooled cake. Decorate with sprinkles.