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featured au gratin potatoes.
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5 from 3 votes

Au Gratin Potatoes Recipe

These homemade au gratin potatoes are baked in a rich, creamy sauce and make for the perfect side dish for this year's holiday table!
Step-by-step photos can be seen below the recipe card.
Prep Time15 minutes
Cook Time1 hour
Total Time1 hour 15 minutes
Course: Side Dish
Cuisine: American, French
Servings: 8
Author: Becky Hardin

Equipment

  • 9x13 Baking Pan

Ingredients

  • 3 lbs Yukon Gold potatoes thinly sliced (about 12 potatoes)
  • ½ yellow onion thinly sliced
  • 4 tbsp unsalted butter (½ stick) plus more for greasing the pan
  • 2 cloves garlic minced
  • ¼ cup all-purpose flour
  • 1½ cups whole milk
  • 1 tsp kosher salt
  • ½ tsp ground black pepper
  • 1 cup freshly shredded cheddar cheese
  • 1½ cups freshly shredded gruyere cheese divided
  • ½ cup freshly grated Parmesan cheese

Instructions

  • Preheat oven to 350°F. Grease a 9×13-inch baking pan with butter.
  • Layer the potatoes and onions in the baking dish. Set aside.
  • In a medium saucepan, melt the butter over medium heat. Add in the garlic and cook until fragrant.
  • Sprinkle over the flour and whisk until smooth and the flour is golden, about 1 minute.
  • Slowly pour in the milk while whisking, making sure to quickly whisk out any lumps. Bring to a simmer.
  • Remove from the heat and whisk in the salt, pepper, cheddar, and ¾ cup gruyere until melted. Pour over the potatoes.
  • Cover with foil and bake for 45-60 minutes, or until the potatoes are tender when pierced with a knife in the center of the baking dish.
  • Remove the foil and sprinkle on the remaining gruyere and parmesan cheese. Bake for 15-20 minutes until the cheese is melted and bubbly.
  • Optional: To brown the cheese, broil for 1-2 minutes.
  • Garnish with herbs and serve.

Video

Notes

  • Shred your own cheese from a block for the smoothest sauce. Pre-shredded cheese is coated in starches that can cause the sauce to become grainy!
  • A runny sauce usually means it didn’t simmer long enough to activate the roux. Let it bubble gently for a few extra minutes until it thickens to coat the back of a spoon. If it’s still thin, whisk 1 tsp of flour into 2 tbsp of warm milk and stir it in.

Nutrition

Serving: 1serving | Calories: 413kcal | Carbohydrates: 37g | Protein: 18g | Fat: 22g | Saturated Fat: 13g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 6g | Trans Fat: 0.2g | Cholesterol: 67mg | Sodium: 698mg | Potassium: 848mg | Fiber: 4g | Sugar: 4g | Vitamin A: 684IU | Vitamin C: 34mg | Calcium: 488mg | Iron: 2mg