Heat on medium, the grease of your choice in a heavy skillet, such as iron skillet or deep sided skillet of your choice.

Add the flour slowly and whisk until all the lumps have gone. Cook on medium heat about 3-4 minutes to remove the raw flour taste.

I usually don't cook to brown mine, but cook to color of your liking

Add the butter,salt and pepper and mix well. If using salt, taste before adding because some greases are salty and you may not need. Just a matter of taste you prefer.

Slowly add the warm milk stirring constantly to keep from lumping up. Stir until smooth and lump free if any.

Turn heat to medium high to bring to slight boil. Reduce heat to simmer, stirring constantly, cook until thick and smooth. If you like thinner gravy, you can add more milk if desired.

I serve mine over potatoes, pork chops, biscuits, country fried steak etc.. Whatever you like gravy on :)