Go Back
easy-au-gratin-potatoes-recipe
Print

Au Gratin Potatoes

Course Side Dish
Cuisine American
Keyword au-gratin-potatoes, best-au-gratin-potatoes-recipe
Prep Time 25 minutes
Cook Time 1 hour
Stand time 10 minutes
Total Time 1 hour 35 minutes
Servings 10 servings (may vary)
Calories 328kcal

Ingredients

  • 3 1/2-4 lbs russet potatoes (peel intact) 1/8 inch slices
  • 4 Tbsp salted butter
  • 1 small onion finely diced
  • 3 Tbsp all purpose flour
  • 1 tsp salt
  • 1 tsp black pepper
  • 1/2 tsp ground mustard
  • 1/8 tsp ground nutmeg
  • 1 large clove garlic finely minced
  • 1 Tbsp fresh thyme leaves plus additional for garnishing
  • 2 cups whole milk or half and half
  • 2 cups shredded Gruyere cheese divided use
  • 1/4 cup grated Parmesan cheese, plus 2-3 Tbsp for the top

Instructions

  • Preheat oven to 375°F. Butter an 11 x 8 inch (2.5 quart baking dish) or similar size baking dish with 1 Tablespoon of butter. Set aside.
  • Thoroughly clean potatoes and using a mandolin slice 1/8 inch slices.
  • To make sauce: In a heavy bottomed saucepan, melt butter over medium heat. Add onion, cooking for 1-2 minutes or just until softened. Add garlic, cook for 1 minute. Add flour, stir until butter is absorbed.
  • To the flour add salt, black pepper, ground mustard and nutmeg. Gradually whisk in milk. Add thyme. Bring to a light bubble then immediately lower the heat to simmer for 3-5 minutes, stirring occasionally.
  • Remove from heat. Add 1 cup Gruyere and 1/4 Parmesan cheese to sauce, Mix until melted.
  • To assemble: Layer 1/2 potato slices fanned and overlapping in baking dish. Spread 1/2 sauce evenly over potatoes.
  • Repeat remaining potatoes, spread with sauce. Sprinkle top with remaining Gruyere and sprinkle with 3 Tablespoons of Parmesan.
  • Cover with foil and bake for 50-60 minutes. Uncover, increase oven temperature to 400 °F. Bake for another 20 minutes or until the top is golden and the potatoes are fork tender.
  • Let stand 5-10 minutes of the sauce to thicken then serve garnished with fresh thyme.

Nutrition

Serving: 1serving | Calories: 328kcal | Carbohydrates: 34g | Protein: 14g | Fat: 16g | Saturated Fat: 9g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 4g | Trans Fat: 0.2g | Cholesterol: 49mg | Sodium: 528mg | Potassium: 784mg | Fiber: 2g | Sugar: 4g | Vitamin A: 527IU | Vitamin C: 11mg | Calcium: 377mg | Iron: 2mg