Macaroni and Cheese

8 ounces elbow macaroni, cooked and drained2 tablespoons butter2 tablespoons all-purpose flour1 cup evaporated milk1 cup water1 egg beaten1 teaspoon salt1 pound Velveeta, cubedIn a large saucepan melt butter over low heat. Whisk in flour and stir for 1 minute. Gradually whisk in the milk and water until smooth. Continue stirring over medium heat until sauce just boils and starts to thicken. Whisk in egg and salt; stir in cheese cubes and stir until melted.Heat oven to 400 degrees.Place cooked noodles in a buttered casserole dish; stir in cheese sauce and bake 20-30 minutes, until edges bubble and top begins to brown.Serves four to six.Cook's notes: This recipe can be prepared one to two days ahead and frozen; it can be doubled.Nutrition values per serving: 387 calories, 14 g fat (8 g saturated), 42 g carbohydrates, 1 g fiber, 25 g protein, 74 mg cholesterol, 1,582 mg sodium.