Classic Wisconsin Macaroni and Cheese

12 ounces elbow macaroni
3 tablespoons butter
1/4 cup diced white onion
2 tablespoons flour
2 cups milk
1 teaspoon salt
1/2 teaspoon pepper
1/2 teaspoon hot pepper sauce
1 tablespoon prepared mustard
3 cups (12 ounces) sharp Wisconsin Cheddar cheese, shredded
3 cups coarse bread crumbs

Preheat oven to 375 degrees F. Cook macaroni according to package instructions, or until al dente. Drain, rinse, and set aside.

In large saucepan, saut? onion in butter for two minutes until transparent. Blend in flour, stirring well to incorporate, and cook for an additional minute. Whisk milk into butter and flour mixture. Bring to simmer and cook until sauce thickens. Reduce to low heat and add salt, pepper, hot sauce and mustard. Stir in 2 1/2 cups cheese.

Add cooked macaroni to cheese sauce and mix well. Place macaroni mixture in buttered, ovenproof, 9-inch square dish. Top with remaining 1/2 cup of Cheddar cheese and bread crumbs.

Bake for 25 minutes, or until top is golden brown.

Serves 4.