I got this recipe from Good Things Catered. It is a great and easy macaroni and cheese, well shells and cheese. My kids couldn't get enough of it. Oh and this recipe makes a ton so I'm going to cut it in half next time I make it.
Shells and Cheese
1 lb medium shells pasta (Barilla pasta holds it's shell shape well)
16 oz block Velveeta (I used the lower fat 2% milk kind)
1/4 cup butter
2/3 cup 2% milk
1 teaspoon garlic salt
ground pepper, to taste
Cut Velvetta and butter into small cubes and set aside.
Boil pasta according to package directions; when done, drain, and put pasta back in pot with a little bit of the cooking water. Mix velveeta cubes, butter cubes, and 1/3 cup milk into the pasta. Fold in until everything melts and becomes creamy. Add garlic salt and ground pepper to taste. Slowly add the remaining milk until desired consistency is reached.