01 - Preheat the oven to 350°F. Grease and flour a 9-inch round or square cake pan.
02 - In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
03 - In a large bowl, cream the butter and sugar together until light and fluffy, about 3 minutes.
04 - Beat in the eggs, one at a time, mixing well after each addition. Stir in the vanilla extract.
05 - Gradually add the dry ingredients to the wet mixture, alternating with buttermilk. Begin and end with dry ingredients. Mix until just combined; do not overmix.
06 - Toss the chocolate chips with 2 tablespoons flour and gently fold them into the batter.
07 - Pour the batter into the prepared pan. Smooth the top and sprinkle with coarse sugar or extra chocolate chips if desired.
08 - Bake for 35–40 minutes, or until a toothpick inserted in the center comes out clean or with a few moist crumbs.
09 - Allow the cake to cool in the pan for 10 minutes, then turn onto a wire rack to cool completely. Slice and serve.