Homemade Macaroni and Cheese

I know this wasn't on the schedule but I was craving this last night so I made it. This was a family favorite growing up. I never make mac and cheese from the box. This is just too good to ever go back to that.

Homemade Macaroni and Cheese
2 cups macaroni (shells, elbow,etc.), cooked and drained
3 T flour
3 T butter
2 cups milk
2 cups shredded cheddar cheese

Over medium heat melt the butter and blend in the flour. Slowly whisk in milk. Cook and stir until think. Add 1/2 tsp. salt and dash of pepper. Stir in cheese until melted. Add noodles. Serve.