Cupcake Coklat Susu dengan Krim Mentega Alpukat

Bahan-bahan (6 porsi)

• 1 cup cake flour
• 2/3 cup sugar
• 1/3 cup cocoa powder
• 1 pinch of baking soda
• 1 pinch of salt
• 3/4 cup water
• 1/3 cup oil
• 1 egg, beaten
• 1 teaspoon vinegar
• 1/2 an avocado
• 1/2 tablespoon butter, softened
• 1 1/4 cup powdered sugar
• 1/2 teaspoon vanilla