In a large skillet, cook the sausage, breaking the meat up with a spoon or spatula, until cooked and crumbled. Drain fat if necessary.
In a large saucepan, melt the butter over medium heat. Whisk in the flour until smooth to make the roux. Cook the roux, stirring often, until lightly golden and frothy (approx. 2 minutes).
Whisk in the milk and cream. Cook, stirring or whisking constantly, 5-10 minutes until gravy thickens to desired consistency.
Add the sausage, salt, and pepper. Taste for seasoning.
Yields 24 servings at 1/4 cup per serving.