Ingredients:

  • 3 cups (375g) all-purpose flour
  • 2 cups (400g) granulated sugar
  • 1 tbsp (12g) baking powder
  • 1/2 tsp (3g) salt
  • 3/4 cup (170g) unsalted butter, softened
  • 3 large (150g) eggs, room temperature
  • 1 cup (240ml) buttermilk, room temperature
  • 2 tsp (10ml) vanilla extract
  • 1/4 cup (60ml) vegetable oil
  • 1 1/2 cups (340g) unsalted butter, softened
  • 5 cups (600g) powdered sugar
  • 3 tbsp (45ml) heavy cream
  • 2 tsp (10ml) vanilla extract
  • 1 pinch (1g) salt

Instructions:

  1. Preheat your oven to 350°F (175°C). Grease your 9x13 inch pan thoroughly with butter or non-stick spray and line the bottom with parchment paper.
  2. Cream the softened butter and sugar together until the mixture looks pale and fluffy.
  3. Beat in the eggs one at a time, then stir in the vanilla and oil.
  4. Gradually fold in the flour, baking powder, and salt, alternating with the buttermilk. Mix until just combined.
  5. Pour the batter into the prepared pan, smoothing the top with a spatula. Bake for 30-35 minutes until the edges pull slightly away from the pan and a toothpick inserted in the center comes out with only a few moist crumbs.
  6. Let the cake cool completely in the pan.
  7. Beat the butter until creamy, then slowly add powdered sugar and heavy cream. Whip on high until the frosting is airy and white.
  8. Spread a thick layer of frosting across the cooled cake using an offset spatula.