Grease a 1? quart casserole dish.

Blend the Milk and Water into the Cream of Mushroom soup in this dish.

Stir in the Tuna, Cheddar Cheese, Dry Mustard, Salt, Rice, and Peas.

Blend the melted Butter with the Bread Crumbs to make a topping. You can use as much or as little as you like; just make sure that at least the entire top is covered to keep the casserole from bubbling over in your oven.

Bake at 400? for 25 minutes. Let cool for 5-10 minutes before serving.