6 medium russet potatoes
6 Tablespoon butter
6 Tablespoon all-purpose flour
2 cup milk
1 cup heavy whipping cream
1 teaspoon salt
2 clove garlic , minced
1 1/2 teaspoon dried onion flakes
salt and freshly ground black pepper , to taste
3 cup freshly grated sharp cheddar cheese ,or Gruyere, or half of each)
Peel the potatoes if you'd like. Slice the potatoes into very thin 1/8'' slices.
In a small saucepan over medium heat, melt butter and stir in flour until smooth. Cook 1-2 minutes, stirring constantly.
Slowly stir in the milk, cream, minced garlic, dried onions, and season with salt and pepper. Cook sauce on low until smooth and boiling, stirring occasionally with a whisk.
Reduce heat and stir in 2 cups of shredded cheese until melted and smooth. Tastes sauce and add additional salt, pepper, garlic or onion flakes, if desired.
Place half of the sliced potatoes in a lightly greased 8x8 inch (or similar size) casserole dish. Pour half of the cheese sauce over potatoes.
Layer the remaining potatoes on top. Spoon the remaining cheese sauce over the potatoes. Sprinkle remaining cheese on top.
Cover with tinfoil and bake at 350 degrees F for 30 minutes.
Remove tinfoil and continue baking, uncovered, for another 20-30 minutes more or until potatoes are cooked, cheese is browned and sauce is bubbly.
To make ahead:
To make Potatoes Au Gratin in advance, prepare the recipe up until baking. Cover with tinfoil and refrigerate overnight. Allow them to rest on your counter for 20 minutes before baking.