Mix flour, baking powder and salt together; cut in shortening; add milk. Stir only until moistened. Turn out onto floured board and knead about 12 times. Pat out dough and cut out biscuits. Place on ungreased cookie sheets. Bake 450°F until golden brown.
Heat oil in deep skillet. Stir in enough flour to make a thick paste (I use a wooden spoon). Add milk quickly. Cook over low heat, stirring constantly. Stirring is necessary to avoid lumping. If lumps do form you can remove them with a slotted spoon. Stir constantly, being careful to cover entire skillet until gravy thickens to the desired consistency.
Season at any time during the cooking providing you don't stop stirring.
Add meat or eggs (these must be prepared prior to starting your gravy) during the last minutes of cooking.