HEAT THE OVEN TO 450F. Combine flour, baking powder, salt and pepper in a large mixing bowl. Cut in the vegetable shortening using a pastry blender or two knives until the mixture has the consistency of coarse crumbs. Add the chilies, cheese and milk, adding more milk if necessary so the dough is pliable but is still wet. Turn the dough onto a heavily floured surface, and knead it lightly (8 to 10 times). Do not overwork the dough. Roll the dough to an even thickness of 3/4-to-1 inch, and cut out biscuits with a 2-inch round cutter (the diameter of a juice can), dipping the cutter in flour between cutting each biscuit so they do not stick. Place the biscuits on an ungreased cookie sheet and bake in the center of the oven for 12 to 15 minutes, or until golden brown. Serve immediately, or bake up to 2 hours in advance and reheat for 5 minutes in a 300F oven. Makes 12 to 14.