Frosted Funfetti Layer Cake

INGREDIENTS

3 cups

cake flour

2 1/2 cups

granulated sugar

1 tbsp

baking powder

1 tsp

salt

1 1/2 cups

unsalted butter, softened and cut into cubes

1 1/4 cups

whole buttermilk, divided

large eggs

2 tsp

vanilla extract

1 cup

confetti quin sprinkles

2 cups

unsalted butter, room temperature

3 3/4 cups

powdered sugar

1/4 cup

heavy cream, more or less as needed

vanilla bean, seeded

food coloring (optional)