In a sauce pan melt butter over medium low heat then add the flour a little bit at a time while whisking to make a roux. Heat the broth. Next add the broth to the roux, stir with the whisk. This will thicken as it heats. Next add a little cream watch for consistency.Bring 4 cups water to a boil in a separate pot, add salt, and pasta.
In the other pot add shredded cheese a 1/4 of a cup at a time while stirring with a spoon. When you have about one cup of cheese in you can add the rest of the cheese.
Cook the pasta al dente. Strain and combine with the cheese sauce.Pour the mix into a casserole and bake uncovered in a preheated oven set to 350°F for about 10 minutes. **Optional, you can mix melted butter and bread crumbs and sprinkle lightly on top.
Keep an eye on the mac & cheese, you want it to brown around the edges and in patches on top.