Grease muffin pans and place 1/2 teaspoon of butter and 1 teaspoon brown sugar in each cup. Sift flour, baking powder, salt and cinnamon together. Beat egg; add milk, shortening and remaining 1/2 cup brown sugar. Add to sifted dry ingredients, stirring only enough to dampen all the flour. Fill prepared muffin pans 3/4 full and bake in hot oven (425 degrees) for 20 minutes. Makes 18. If desired, chopped nuts or raisins may be added to the butter and brown sugar of the cup.