In another small bowl mix the buttermilk with the two eggs and vanilla extract.
Add the blueberries and the chocolate chips to the flour mixture and toss them around.
In a large bowl add the all purpose flour and cake flour. To it add the baking powder, sugar and salt. Mix it all together. Using a pastry blender or a fork, cut in the butter in the flour until it resembles small peas.
Preheat oven to 375 F degrees. Line a baking sheet with parchment paper.