Cook the sausage in a large, deep skillet over medium heat until evenly brown. Let them drain on paper towels, setting aside 2 tablespoons of their fat in the skillet. Stir the flour, salt, and pepper into the skillet. Cook while stirring constantly until the flour is brown.

Add in the chopped green onion and cook until it's tender. Gradually stir the in milk and continue cooking until thickened. Add some extra milk if you want it thicker. Serve with the prepared sausage and, preferably, some biscuits.