Whisk together the flour, baking powder, baking soda, salt, sugar, garlic powder and cayenne in a large bowl. Cut in the butter until mixture resembles coarse crumbs. I have my butter very cold and grate it with a hand grater into the flour.
Add pimentos and cheese to flour mixture and stir in buttermilk with a spoon (you can use more or less buttermilk just until you have a ball of dough you can pickup). Put dough out onto a floured surface and cut into biscuits.
Place biscuits on a baking sheet close together and brush tops with either melted butter or buttermilk. I use buttermilk. Sprinkle on smoky paprika. Bake in preheated 425 degree oven for 12 to 15 minutes until brown on top. Makes 18 biscuits.
I make the dough about 3/4 to an 1 inch thick and get as many biscuits as I can, then if there is extra, I pat it out again and start over. I do this several times.