When I bake it, I always add strips of American Cheese (the real stuff, not "American Cheese Food"! whatever that is?), to the top, then sprinkle some buttered breadcrumbs on top of that...
I also prefer to use a mild cheddar, it makes for a creamier cheese sauce... sharp & esp. ex. sharp tend to be grainy...
I actually prefer using the small pasta shells as opposed to macaroni, or wagon wheels...
they have more surface area for the cheese sauce to stick to...
This is the basic recipe I use for a Creamy Mac & Cheese (the evaporated milk is what makes it really creamy!):
Ingredients
1 tablespoon salt
1 pound elbow, shell or other bite-size shaped pasta
2 (12 fluid ounce) cans evaporated milk
1 cup chicken broth
1 tablespoon Worcestershire sauce
3 tablespoons butter
1/3 cup flour
1 1/2 tablespoons Dijon mustard
1/2 cup grated Parmesan cheese
Freshly ground black pepper
1 pound grated mild cheddar cheese
Directions
1. Bring 2 quarts of water to boil in large soup kettle.
Add salt and pasta.
Using package directions as a guide, cook until al dente.
Drain. To prevent sticking, drain and immediately pour onto a large lipped baking sheet and let cool while preparing sauce.
2. Meanwhile, microwave the milk and chicken broth in a 4-cup Pyrex measuring cup or bowl until hot and steamy (not boiling).
Melt butter in the empty pasta pot; whisk in flour, then hot milk mixture.
Continue to whisk until thick and bubbly, 3 to 4 minutes.
Whisk in mustard, Worcestershire, Parmesan and pepper. Turn off heat, stir in cheddar until melted.
3. Add drained pasta to sauce, and stir until everything is well combined over low heat.
Stir to heat through, and thin with a little milk if the sauce is too thick. Serve hot.