In a medium saucepan, heat milk over very low heat, stirring occasionally. Make sure to keep an eye on the milk, don’t let it boil.
Meanwhile, in a large skillet, heat the butter/margarine over medium high heat until melted, then add sausage. Crumble and cook the sausage until well-browned and no longer pink.
Sprinkle flour over the sausage and cook, stirring, for a minute or two.
Add warm milk all at once and cook, stirring, until thickened and bubbly.
Turn heat all the way down, add paprika (if desired) and season well with salt and pepper, stirring and tasting frequently until the flavor is to your liking. Turn off the heat. Gravy will continue to thicken as it cools. Serve over warm biscuits.