Potato gratin (big)

Note: These recipes use NZ measurements. 1 c = 1 cup = 250 ml. 1 T = 1 tablespoon = 15 ml. 1 D = 2 teaspoons. 1 t = 1 teaspoon = 5ml. If you're in America, you may find you need a little extra baking powder in recipes that use it.

2.5 lb potatoes, thinly sliced
3 T butter
3 T flour
2 cups milk
1/2 cup cheese
1/2 cup cheese
Optional: cubed ham

Layer sliced potatoes with salt, pepper and optionally ham in large baking dish. Pour cheese sauce over layers. Top with extra grated cheese and breadcrumbs.
Bake at 370 F for one hour, until potatoes are cooked and top is golden brown.

Source: Hadley and Jeff original