15 Minute Mac and Cheese

Mac and Cheese is a food that warms the soul and is one of my family's favorites.  I have several recipes for Mac and Cheese ranging from the 15 cheddar cheese version featured here today to the elaborate chicken and prosciutto version I break out for a special occasion.
I used to make the blue box Mac and Cheese weekly, but I've recently discovered making it from scratch takes only a few minutes more!  This recipe whips up quickly with just 15 minutes of work time.  In total it will probably take you anywhere from 30-45 minutes depending on whether or not you bake it.

Ingredients
8 oz elbow macaroni, rotini or penne pasta
2 cups cheddar (or a combination of cheddar, mozz, swiss...any easy melting cheese)
2 cups milk
1/2 cup diced onion
1 clove minced garlic
1 TBSP dijon mustard
1/4 TSP cayenne pepper
4 TBSP butter
4 TBSP flour
1/4 cup Parmesan cheese (optional)
1/4 cup bread crumbs (optional)
salt and pepper to taste

Directions
In a 5 qt, or large, pot cook off the pasta to the package directions.  Preheat the oven to 350 degrees if you plan on the oven finish.  Drain the pasta and set aside.  Using the same pot* saute the garlic, onion and 1/2 tsp salt in the butter over medium heat.  Once softened sprinkle in the flour and stir it in.  Cook until all the flour has dissolved and slowly stream in the milk constantly stirring (you can use a whisk for this if you prefer).  Once combined add in the dijon, cayenne.
When the mixture comes to a bubble (this should take 3-5 minutes) start adding the cheese, 1/2 cup at a time.  Stir or whisk in each addition until is has completely melted before adding the next.  Season sauce to taste.  Take the cheese sauce off the heat and stir in the cooked pasta.
At this point you can serve it up** or continue to the oven finish. 
Oven finish.  Pour the Mac and Cheese into a 3 qt glass or stone baking dish.  Top with breadcrumbs and Parmesan cheese.  Bake, uncovered, for 20 minutes.  Allow to cool for 5 minutes before serving and enjoying!