This is an easy one from Cooks.com

CRABMEAT AU GRATIN CASSEROLE



1 stalk celery, chopped fine
1 c. onion, chopped fine
1/4 lb. butter
1/2 c. all-purpose flour
1 can evaporated milk (13 oz.)
2 egg yolks
1 tsp. salt
1/2 tsp. red pepper
1/4 tsp. black pepper
1 lb. white crabmeat
1/2 lb. grated American cheese

Saute onions and celery in butter until onions are wilted. Blend flour in well with this mixture. Pour in the milk gradually, stirring constantly. Add egg yolks, salt, red and black pepper; cook for 5 minutes. Put crabmeat in bowl suitable for mixing and pour the cooked sauce over the crabmeat. Blend well and then transfer into a lightly greased casserole and sprinkle with grated American cheese. Bake at 375 degrees for 10-15 minutes or until light brown. Serves 6.