Cauliflower Au Gratin

20 pounds cauliflower, frozen
4 1/2 tablespoons salt
3 gallons boiling water
1 gallon milk
1 pound butter or margarine, melted
2 1/4 cups all-purpose flour, sifted
2 tablespoons salt
5 cups (1 pound 8 ounces) cheese, grated
6 cups dry bread crumbs
1 cup butter or margarine, melted

Add 4 1/2 tablespoons salt to boiling water. Add cauliflower to salted water. Bring to a boil; cover. Simmer 12 minutes or until cauliflower is tender. Drain. Place 1 1/2 gallons cauliflower in each pan.

Blend butter or margarine and flour together, stirring until smooth. Add roux to milk, stirring constantly. Simmer 5 minutes or until thickened. Season with 2 tablespoons salt as needed. Add cheese; stir until blended.

Pour 2 1/2 quarts sauce over cauliflower in each pan.

Mix crumbs and butter or margarine. Sprinkle over cauliflower.

Heat oven to 350 degrees F. Bake 15 minutes or until crumbs are browned.

Yields 100 (1/2 cup) portions