4 to 5 medium russet potatoes (about 2 lbs.)
3 tablespoons butter
3 tablespoons flour
3/4 teaspoon sea salt
a few grinds of fresh pepper
1 teaspoon onion powder (optional)
2 1/2 cups milk
1 to 1 1/2 cups diced ham or 1 (6 ounce) can
1 tablespoon additional butter
Preheat the oven to 425 degrees.
In a medium saucepan, melt the butter. Stir in the flour, salt , pepper and onion powder and blend well into a smooth paste. Cook over low heat, stirring constantly about 1 minute. Whisk in the milk and bring slowly to a boil, stirring constantly. Boil and stir for one minute. Remove from heat.
Pare and slice the potatoes very thinly, about 1/8-inch thick. Butter a casserole dish and place half the potato slices over the bottom. Scatter the diced ham evenly over the potatoes and then cover with half the white sauce. Layer the remaining potatoes over the ham and pour the rest of the sauce over the top, smoothing with a rubber scraper to make sure all the potatoes are covered. Dot the top with 1 tablespoon butter.
Cover with a lid or aluminum foil and bake for 30 minutes. Remove the lid or foil, turn the oven down to 375 degrees and bake another 30 to 40 minutes until potatoes are tender and the top is golden brown.
Serves 4 - 5.
Variation: For a vegetarian version, skip the ham and add 1 cup of cheddar cheese to the hot white sauce, stirring until melted. Now you have Potatoes Au Gratin.