Cheesy Au Gratin Potatoes

  • Author: KrazyKitchenMom
  • Prep Time: 15 minutes
  • Cook Time: 90 minutes
  • Total Time: 1 hour 45 minutes
  • Yield: 6-8 servings 1x


Get ready for your family to devour these Cheesy Au Gratin Potatoes. They are cheesy, creamy, yummy potatoes. They will instantly become a family favorite.



  • 4 large russet potatoes, washed, peeled and sliced thin. (These can be sliced by hand but if you have a mandolin you can get a much more consistent slice.)
  • 1/2 large onion, peeled and sliced into thin rings (same size as the potatoes)
  • 3 TBS flour
  • 3 TBS butter
  • 2 cups of milk
  • 2 cups of shredded sharp cheddar cheese
  • 1 teaspoon dry mustard
  • 1/2 teaspoon ground sage
  • 1/4 teaspoon nutmeg
  • Salt and Pepper to taste


  2. Preheat oven to 400 degrees.
  3. Spray a large casserole dish with non-stick cooking spray.
  4. Start with potatoes and place a layer covering the bottom of the dish, next layer with onions, again with a layer of potatoes and continue until all onions and potatoes are in the casserole dish. Set aside.
  5. In a saucepan on the stovetop, melt butter on medium, add flour and whisk, about 2 minutes, add milk and continue whisking constantly until the mixture begins to thicken (this may take 3-5 minutes).
  6. Add dry mustard, ground sage, and nutmeg.
  7. Add the cheese and once the cheese is fully incorporated, remove from heat.
  8. Pour the cheese mixture over the potato/onion layers.
  9. Cover with foil and bake for 1.5 hours.
  10. Remove from oven, remove foil, and place it back into the oven on broil until they brown.

  • Category: Side dish
  • Method: baked
  • Cuisine: American

Keywords: Holiday side dish, cheesy potatoes