In a saucepan, fry sausage patties, drain and keep warm. [I prefer to use my 3-qt saute pan.] Pour off all but two tablespoons grease. Blend in flour and brown, stirring constantly. [I don't like to let the roux get much past the yellow-gold stage.] Gradually add milk or water, mixing well. [I prefer milk.] Bring to a boil, reduce heat and simmer. Crumble sausage patties and add to gravy along with salt and pepper. Simmer two minutes. Serve over hot open-faced biscuits.