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classic potatoes au gratin

Classic Potatoes Au Gratin

Steven Pennington
Creamy cheesy potato recipe that everyone loves
5 from 4 votes
Prep Time 6 mins
Cook Time 1 hr
Total Time 1 hr 6 mins
Course Casserole
Cuisine Classic French
Servings 8 Servings


Bechamel Ingredients

  • 3 tablespoon All-Purpose Flour
  • 4 tablespoon High-Quality Butter
  • 2 ½ Cups Whole Milk / plus more to help control the thickness
  • 7 Cloves
  • pinch Nutmeg
  • ½ Onion / kept whole/ cloves attached
  • ½ teaspoon Thyme
  • ½ teaspoon Minced Garlic

Potatoes Au Gratin Ingredients

  • 4 medium Russet Potatoes
  • 1 ¼ cups Gruyere Cheese or Swiss /shredded
  • Salt & Pepper - to taste
  • ½ whole Onion - Julianne Cut / Julianne cut onion, long thin slices.



  • Flavored ROUX: First, melt butter over medium-high heat, then add the garlic and toast, following with the flour and coat all the flour in the butter.
  • "Cook-Out" the flour. Allow the flour to absorb the butter. This will help ensure the bechamel sauce will not be grainy.
  • Next, add in half of the milk and stir constantly. The sauce will try to thicken. Add the remaining milk at this point, little by little. Keep stirring. Allowing the milk to come to a soft boil. (Soft boil means the bubbles are breaking the surface, but not a full boil)
  • Once at a soft boil, turn off the heat. The sauce will thicken. If the sauce gets too thick for your purposes add a little more milk to thin out the sauce. Remember the heat activates the Roux and thickens.
  • Add the Nutmeg, to taste. Stir and incorporate
  • Next, add the "half" Onion with the Cloves attached to the onion.
  • Cover the pot for a few minutes to allow the flavors to develop.

Prepping the Potatoes

  • First, wash off the potatoes well. Using a mandolin or sharp knife, make thin slices. The thickness choice is up to you. I suggest ⅛ inch slices. Remember the potato skin is where most of the health benefits reside. I took a peeler and removed only part of the skins. Made peeled stripes going down the length of the potato in an alternating pattern. It helps with the presentation. See Video Above./Below

Making the Potatoes Au Gratin

  • First, pour Bechamel sauce covering the bottom of your casserole dish. Using glass-bakeware is suggested for even cooking. The bechamel sauce acts to protect the potatoes from burning and sticking. Next, add two layers of potatoes. Lay the potatoes out with each potato slightly covering the last potato. Shingle pattern. Then add a layer of cheese and cover it with Bechamel sauce. Add a small amount of salt & pepper, cheese of your liking, and julienne cut an onion for more flavor and texture. Repeat the process till you've filled your bakeware to the desired level. Add the remaining Bechamel sauce, allow for the potatoes to stick out a small amount. Don't drown the potatoes in sauce, helps with presentation. Cover with more cheese and place on a cookie sheet to prevent bubbling over.


  • Preheat Oven 375 (could do 400) both work
  • Cook for 45 to one-hour plus or till done. All ovens are different and the depth of everyone's cookware will be different.
  • Test for doneness. Poke with a fork. If soft enough, turn on the broiler to brown the top. Be sure to keep an eye on this process as the potatoes au gratin could burn. Crack the oven door so you can see what's happening.
  • Allow to cool for 5-10 minutes and enjoy it.


Keyword Classic Potatoes Au Gratin
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