Country Potato Gratin

This is a good recipe to use up leftover holiday ham. A little bit of ham goes a long way. Notice that the dish bakes for awhile.

Ingredients
2 tsp butter
1 medium onion thinly sliced
3 garlic cloves, minced
4 cups 2% reduced-fat milk
1 teaspoon salt
1/4 teaspoon freshly ground black pepper
2/3 c flour
1.5 c shredded sharp cheddar cheese, divided
1.25 c diced ham
3 pounds baking potatoes, cut into 1/8-inch-thick slices

1. Preheat oven to 350°.
2. Melt butter in a Dutch oven over medium-high heat. Add onion and garlic; sauté 5 minutes or until onion is tender. Combine milk, salt, pepper, and flour, stirring with a whisk. Add milk mixture to pan. Bring to a simmer; cook until slightly thick (about 2 minutes), stirring frequently.
3. Add half of cheese and all ham, stirring until cheese melts.
4. Stir in potatoes.
5. Place the potato mixture in a 13 x 9-inch baking dish coated with cooking spray. Sprinkle potato mixture with remaining cheese.
6. Cover with foil coated with cooking spray. Bake at 350° for 45 minutes. Uncover and bake an additional 30 minutes or until lightly browned and potatoes are tender. Let stand 15 minutes before serving.