Confetti Birthday Cake (Funfetti)

Bahan-bahan (12 porsi)

• 3 and 3/4 cups (443g) cake flour (spooned & leveled)
• 1 teaspoon baking powder
• 1 teaspoon baking soda
• 1 teaspoon salt
• 1 and 1/4 cups (282g) unsalted butter, softened to room temperature
• 2 cups (400g) granulated sugar
• 1/3 cup (80ml) vegetable oil
• 4 large eggs, at room temperature*
• 2 large egg whites, at room temperature*
• 3 teaspoons (15ml) pure vanilla extract
• 1 and 1/2 cups (360ml) buttermilk, at room temperature*
• 3/4 cup (135g) rainbow sprinkles*
• 1 and 1/2 cups (340g) unsalted butter, softened to room temperature
• 5 and 1/2 cups (650g) confectioners’ sugar
• 1/3 cup (80ml) heavy cream, at room temperature
• 3 teaspoons (15ml) pure vanilla extract (or use clear imitation vanilla extract for stark white frosting)
• 1/8 teaspoon salt
• optional: additional sprinkles for garnish