1 teaspoon bacon grease
1/2 cup butter
1/2 cup all-purpose flour
1/2 cup diced onion
1/2 cup sliced fresh mushrooms
1/2 cup sliced green onions
1/2 cup chopped celery
1/2 cup shredded mozzarella cheese
Preheat oven to 350 degrees F (175 degrees C).
In a medium saucepan, cook bacon grease over medium heat until crisp.
In a large bowl, mix butter, flour, onion and mushrooms. Pour over chicken and vegetables. Transfer to a 9x13 inch baking dish.
Bake in preheated oven until chicken is done and veggies are tender, about 15 minutes.
In a medium bowl, mix the flour mixture with mushrooms, green onions, celery and cheese. Pour mixture over chicken and vegetables. Sprinkle with chicken and vegetables and sprinkle with bacon grease.
Bake uncovered at 350 degrees F (175 degrees C) for 30 minutes.