Vanilla Cupcakes with Chocolate Frosting

Ingredients

• ½ cup (1 stick or 113g) unsalted butter (at room temperature)
• ¾ cup (155g) granulated sugar
• 1 large egg + 1 large egg white (at room temperature)
• 2 teaspoons vanilla extract
• 1 teaspoon vanilla bean paste
• 1⅔ cup (190g) cake flour
• 1 teaspoon baking powder
• ½ teaspoon baking soda
• ¼ teaspoon salt
• ½ cup (120g) sour cream (at room temperature)
• ½ cup (120ml) buttermilk (at room temperature)
• 8 oz (1 block or 227g) cream cheese (at room temperature)
• 1/2 cup (1 stick or 113g) unsalted butter ( at room temperature)
• 3 cups (340g) powdered sugar
• ½ cup (43g) cocoa powder
• 2 Tablespoons milk or heavy cream
• 1 teaspoon vanilla extract