Chicken and Potato bake

200g Sliced Mushrooms
Butter
100g Chopped Onions
200g Cooked Diced Chicken
200g Cooked Diced Potatoes
1tbl Flour
200ml Milk
Salt
Pepper
Bread Crumbs for topping

1] Heat butter in a heavy frying pan; sauté mushrooms and onions until tender and lightly browned.
2] Stir in flour until dissolved.
3] Gradually add milk, stirring until thickened.
4] In a lightly buttered casserole dish, combine chicken, potatoes, and mushroom mixture, along with the salt and pepper. Top with bread crumbs. Bake at 350° for 20 to 30 minutes.