My wife is the sausage gravy master. She uses one half package each of Jimmy Dean hot and regular sausage, the kind sold in a plastic encased tube. After frying she sets it aside saving the grease and little bits in the pan. With today’s lean sausage she adds some cooking oil and a couple of tablespoons of flour. Over a medium high heat she then uses a wooden utensil and mixes the flour and grease/oil mixture into a dark roux. Add one cup of milk and stir constantly until it starts to thicken, as it thickens continue adding milk until desired consistency. Add the sausage back in and you are good to go. It’s going to be trial & error the first couple of times but after that it’s easy.
The potatoes are simple. I cut fresh potatoes into ¾ - 1” chunks, cover, and fry in lard in a pre heated skillet over medium high heat. You can use cooking oil as well. You have to play with the heat, reducing it as you go along. Take the cover off and stir every 3-4 minutes. Once they get soft reduce the heat and leave the cover off, right at the end throw a handful of chopped onions in there. If you do it too soon moisture from the onions will soften the crisp potatoes. This was a small batch; total time was about 20 minutes.