Double Chocolate Chip Muffin Tops

Ingredients

• 2½ cups all-purpose flour
• ½ cup cocoa powder
• 1¼ teaspoons baking powder
• ½ teaspoon baking soda
• ½ teaspoon salt
• 1 stick unsalted butter, at room temperature
• ¾ cup light brown sugar
• ¼ cup sugar
• 1 egg
• 1 teaspoon pure vanilla extract
• 1 cup buttermilk
• 1½ cups semisweet chocolate chips