1 c. chopped onion
1/4 c. flour
1/8 tsp. pepper
1/4 tsp. celery salt
6 c. sliced, cooked carrots
8 oz. American cheese slices
1/4 c. butter
1 tsp. salt
1/4 tsp. dry mustard
2 c. milk
1 c. bread crumbs

Saute onion in butter until glossy. Stir in flour and seasonings until smooth. Slowly stir in milk, cooking over medium heat until sauce thickens. Place half of the cooked carrots in greased baking dish, top with cheese slices. Cover with remaining carrots; pour sauce over all. Bake at 350 degrees for 30 minutes. Sprinkle bread crumbs over carrots; bake 15 minutes more until crumbs are golden brown.