Preheat oven to 350 degrees F (175 degrees C). Line 24 muffin cups with paper liners.
Blend pistachios with 1/2 cup sugar in a blender until finely ground.
Sift all-purpose flour, cake flour, baking powder, and salt together in a bowl.
Beat 1 cup sugar and butter together in a large bowl with an electric mixer until light and fluffy. Beat one egg at a time into the creamy butter mixture, thoroughly integrating each egg before adding the next.
Stir milk and vanilla extract together in a separate bowl.
Alternately stir flour mixture and milk mixture in small amounts into the butter mixture beginning and ending with the flour mixture; stir just until it comes together into a batter. Fold the ground pistachios into the batter. Spoon batter into the prepared muffin cups to about 2/3 full.
Bake in the preheated oven until a toothpick inserted into the center comes out clean, 15 to 18 minutes. Cool in the muffin cups for 5 minutes before removing to cool completely on a wire rack.
