Buttermilk-Chocolate Chip Crumb Cake

INGREDIENTS

• :
• ¾ cup all-purpose flour
• ¾ cup light brown sugar
• ¾ cup cold butter, cut into chunks
• 1 tsp vanilla extract
• 1¼ cup all-purpose flour
• ¼ cup cake flour
• 1 stick butter
• ¾ tsp baking powder
• ¼ tsp baking soda
• ¾ cup mini bittersweet chocolate chips
• ¾ cup granulated sugar
• ½ cup buttermilk
• 1½ eggs
• 1½ tsp vanilla extract
• ¾ cup mini bitter-sweet chocolate chips, for sprinkling on top of the cake
• Powdered sugar, for sifting on top of the cake