Simple High School Graduation Cake for 15

Instructions:

1. Preheat oven to 350°F (175°C) and grease a 9x13 inch baking pan.
2. Cream the softened butter and granulated sugar together using an electric mixer until the mixture is pale and fluffy.
3. Incorporate eggs one by one, then stir in the vanilla extract and vegetable oil.
4. Alternately add the flour, baking powder, and salt mixture and the buttermilk, mixing on low speed until just combined.
5. Spread the batter evenly into the prepared pan and bake for 25 minutes, or until the edges pull away from the pan and the center springs back.
6. Remove from oven and allow the cake to cool completely.
7. Prepare the buttercream by whipping together the butter, powdered sugar, heavy cream, vanilla, and salt until smooth.
8. Frost the cake and decorate using gel food coloring, gold star sprinkles, a fondant graduation cap, and black piping gel for calligraphy.