Au Gratin Potatoes (updated 6/27/21)
3 T butter
1 small onion, halved and sliced
2 T flour
1 tsp salt
2 cups whole milk
1 clove garlic, halved - spear both halves on one toothpick for easy removal from sauce
1 1/4 cups shredded cheese (I like a combo of cheddar, jarlesburg and parmesan)
3 lbs potatoes (red skinned or yukon gold) sliced thin
Make cheese sauce - saute onions in butter until tender, stir in flour and stir until smooth. Add salt, milk and garlic on toothpick, cook and stir until thickened. Add cheese, heat and stir until melted. Remove garlic.
Heat oven to 350. Grease a 9x13 pan and layer 1/2 of the potato slices, top with 1/2 of the cheese sauce, repeat with remaining potatoes and sauce. Cover tightly with aluminum foil and bake for 1 hour. Remove foil and bake for 30 minutes more until browned on top.
Let cool for 10-15 before serving.
Makes 6 servings