4 tablespoons butter
5 tablespoons flour
1 teaspoon salt
1/4 teaspoon pepper
1 cup milk or part chicken broth or mushroom liquid
2 cups cooked diced chicken
1 can (4 ounces) chopped mushrooms, drained
fine dry bread crumbs
1 egg, beaten with 1 tablespoon water
Melt butter in saucepan. Stir in flour, salt and pepper. Continue stirring and gradually add the milk or milk and broth. Cook, stirring, over low heat until smooth and thickened. Blend in chicken and mushrooms.
Spread mixture in an 11x7-inch pan. Chill for 2 hours, or until firm enough to cut into rounds. Using a biscuit cutter, cut into rounds. These can also be chilled then shaped by hand, but the biscuit cutters make them uniform in size.
Coat croquettes with crumbs, then dip in egg and water mixture, coating both sides. Coat again with the bread crumbs. Fry in hot oil at about 370°. Use a deep fryer or heat about 1 1/2 inches of oil in a deep heavy skillet or Dutch oven. Fry croquettes until nicely browned.