1-1/2 lbs gluten-free sausage
6 slices gluten-free bread, cubed with crust
2 cups shredded cheese
6 eggs, beaten
2 cups milk
3/4 tsp dry mustard
1-1/2 cups milk
2 Tbs cornstarch
2 Tbs butter or margarine
1-1/2 tsp gluten-free chicken base or bouillon
1/8 tsp onion powder
Dash of pepper
2 Tbs mayonnaise
1 (4-oz) can sliced mushrooms, drained
In skillet brown sausage; set aside.
In 13×9-inch baking pan or 3-quart casserole dish layer 1/2 of bread cubes, 1/2 of cheese, and 1/2 of sausage. Repeat layer.
Beat eggs; add milk, and dry mustard. Pour over layers in pan or casserole dish.
Make sauce: In saucepan whisk milk and cornstarch until blended. Add butter, chicken base, onion powder and pepper. Cook and stir until thickened and bubbly. Add mayonnaise and stir until well blended. Add salt to taste. Stir in drained mushrooms.
Pour over layers in pan or casserole. Spread evenly over top of casserole. Place in refrigerator overnight.
In the morning bake at 300 degrees for 1-1/2 hours or 350 degrees for 45 minutes.