Cook sausage in frying pan until done. I crumble the sausage up really good with a wooden spoon while it is cooking, gives you more sausage per bite in the gravy. Do Not Drain the grease off, save it. Scoop the sausage out of the pan and place in a strainer with a bowl under it, this will catch the excess grease. Let set for a minute and then add the excess grease back to the pan. (if you do not have a full 1/4 cup from the drippings you can use regular cooking oil to complete it)
Set pan on medium/high heat and add flour, salt and pepper to grease. Stir until flour and oil is well incorporated and flour starts to turn a tan color. (I use a whisk to stir it, helps keep it from lumping up)
While still stirring, slowly add in the evaporated milk and the whole milk. Keep stirring while the gravy cooks and thickens. Add in the sugar, and mix well. Now add back the sausage and blend it in well.
Prepare your biscuits and serve. Hope you enjoy it.