Ultimate Doubly Cheesy Mac 'N' Cheese

I made this yummy recipe the other night with grilled chicken. The secret is to add an extra layer of cheese at the end, then let it melt on top in the oven. Trevor really enjoyed this side dish.

4 tablespoons (1/2 stick) butter, cut into pieces, plus more for the baking dish
1/2 pound uncooked elbow macaroni
3 eggs, lightly beaten
1 cup milk
1/2 cup sour cream
1/2 teaspoon salt
1/2 teaspoon pepper
1/2 teaspoon dry mustard powder
4 cups (1 pound) grated Cheddar cheese

Preheat the oven to 350. Butter a 2-quart flameproof baking dish. In a large pot of boiling salted water, cook the macaroni according to the package directions.

Meanwhile, in a medium bowl, mix together the butter, eggs, milk, sour cream, salt, pepper and mustard.

Drain the macaroni, transfer it to a large bowl, and stir in 2 cups of the cheese. Add the egg-and-milk mixture and stir to combine. Pour into the baking dish and bake for 30 minutes. Top with the remaining 2 cups cheese and put the baking dish under the broiler until bubbly and golden brown. Serve immediately.