Mix flour and baking powder in a bowl. In a large old stoneware bowl beat butter until creamy. Add sugar and beat until pale and fluffy. Add eggs, one at a time, beating after each. Add flour mixture. Mix only until blended. Add buttermilk. Mix only until blended. Sprinkle raisins over batter and fold in.
Using a large ice cream scoop, place mounds of dough on an ungreased cookie sheet about 2 inches apart. Bake at 350 degrees for about 15 minutes, then turn oven to 325 degrees for another 15 minutes. Cool on wire rack. Makes one dozen.