Gerr's Mac and Cheese

1. Heat the oven to 375 degrees.
2. Butter a 3-quart casserole dish; set aside.
3. In a large saucepan over medium heat, melt 2 tablespoons butter.
4. Dice red onion (optional) into tiny pieces and add to butter mixture.
5. In another small saucepan add milk and set over medium heat.
6. Add remaining 6 tablespoons butter into the large saucepan. When butter starts to bubble, add flour, and cook, stirring slowly for one 1 minute.
7. Slowly pour hot milk into flour-butter mixture while whisking. Continue cooking, whisking constantly, until the mixture bubbles and becomes thick.
8. Remove the pan from the heat. Stir in salt, nutmeg, black pepper, cayenne pepper.
9. Slowly add cheddar a bit at a time while constantly stirring mixture. Once melted, set cheese sauce aside.
10. Fill a large saucepan with water. Bring to a boil. Add macaroni; cook 2 to 3 fewer minutes than manufacturer's directions, until outside of pasta is cooked and inside is underdone since casserole will go into the oven.
11. Transfer the macaroni to a colander, rinse under cold running water, and drain well. Stir macaroni into the reserved cheese sauce.
12. Pour the mixture into the prepared casserole dish. Put a few dabs of butter on top of the mixture.
13. Bake until browned on top, about 30 minutes. Transfer dish to a wire rack to cool for 5 minutes; serve.

Source : writergirl56