then reduce to a simmer. ， Step 3: Make the Cheese Sauce In the same skillet， heat bacon drippings over medium heat. Whisk in the flour and stir constantly for 2 minutes to form a roux. Gradually whisk in the heavy cream， thyme， and hot sauce. Bring to a boil， garlic powder， then the milk， a little at a time， to prevent lumps. Stir in mustard powder，。