Skinny Scalloped Ham and Potatoes

Heat oven to 350 degrees F. Spray a 1 1/2 quart casserole with cooking spray.

Melt the margarine in a medium saucepan over medium heat. Mix the flour, mustard, salt and pepper, with a whisk, stir the flour mixture into the melted margarine and whisk until somewhat smooth (if it looks lumpy, don't worry, it will smooth out).

Gradually add the milk stirring with the whisk all the time. Keep whisking until the mixture comes to a boil (this will thicken the sauce). Boil for 1 minute, remove from heat.

Layer half of the potatoes, half of the ham and half of the sauce, then repeat the layering ending with the sauce.

Cover and bake about 1 hour or until potatoes are tender. Let stand about 5 minutes before serving.