Cheesy Baked Mac and Cheese

There are many different recipes I have tried for baked Mac and Cheese and I think this one is my favorite so sharing with you....
The Cheese sauce has a consistency of Broccoli Cheese Soup...
I had to modify a little bit with the ingredients I had on hand...
The recipe called for 1 ( 8 ounce) package of processed American Cheese~Velveeta).

***I did not have so I used 12 unwrapped Velveeta slices...and topped the dish with Bread Crumbs.

Ingredients:
2 Tablespoons of butter
1/4 cup finely chopped onion
2 Tablespoons all purpose flour
2 cups of milk
3/4 teaspoon of salt
1/2 teaspoon of dry mustard
1/4 teaspoon of black pepper
1 (8 ounce) package of elbow macaroni
2 cups of shredded sharp cheddar cheese
***1 (8 ounce) package of Velveeta cheese (cut into strips or cubes)

Directions:
1. Preheat oven to 350 degrees and spray dish with Pam.
2. Melt butter in a medium saucepan over heat and saute onion til tender. Stir in flour and cook 1 minute. Stir in milk, salt, pepper, and mustard, cook and stir frequently. Let mixture thicken and get bubbly.
3. Meanwhile boil noodles.
4. To the milk mixture ~add the cheeses. stir until all cheese melts.
5. Combine macaroni and cheese sauce in a greased baking dish. (can top with bread crumbs)
6. Bake at 350 for 30 minutes or hot and bubbly. Let cool and serve.

Can be made ahead....