1 pkg. (16-oz.) uncooked large elbow macaroni
1/2 c. butter
1/3 c. flour
2 c. milk
3 c. (12-oz.) shredded cheddar cheese, divided
1 container (12-oz.) small-curd cottage cheese
2 large eggs, lightly beaten
1 1/2 tsp. salt
1/4 c. dry breadcrumbs

Cook pasta according to package directions; drain. Melt butter in a Dutch oven over low heat; whisk in flour until smooth. Cook 1 minute, whisking constantly. Gradually whisk in milk; cook over medium heat, whisking constantly, until thickened and bubbly. Stir in 2 cups cheddar cheese and next 3 ingredients. Stir in pasta. Spoon mixture into a lightly greased 13-inch by 9-inch baking dish. Top with remaining 1 cup cheddar cheese, and sprinkle breadcrumbs over cheese.

Bake casserole at 350°F for 30 minutes, or until hot and bubbly.