01 - Preheat oven to 350°F. Grease and flour a 9-inch round or square cake pan.
02 - Whisk together flour, baking powder, baking soda, and salt in a medium bowl. Set aside.
03 - Beat softened butter and granulated sugar in a large bowl until light and fluffy, approximately 3 minutes.
04 - Incorporate eggs one at a time, mixing thoroughly after each addition. Blend in vanilla extract.
05 - Alternately add dry ingredients and buttermilk to the butter mixture, beginning and ending with dry ingredients. Mix until just combined; avoid overmixing.
06 - Toss chocolate chips with 2 tablespoons flour, then gently fold into the batter.
07 - Pour batter into prepared pan, smoothing the surface. Sprinkle with coarse sugar or additional chocolate chips if desired.
08 - Bake for 35 to 40 minutes until a toothpick inserted in the center emerges clean or with minimal moist crumbs.
09 - Let cake rest in pan for 10 minutes, then invert onto wire rack to cool completely before slicing and serving.