Go Back
Baked potatoes au gratin ready to serve

Potatoes au Gratin

Thinly sliced Yukon Gold potatoes layered with a garlic thyme cream sauce and Gruyère, cheddar and Parmesan, baked until golden and bubbly.
Print Recipe Pin Recipe
Prep Time 25 minutes
Cook Time 1 hour 20 minutes
Total Time 1 hour 45 minutes
Servings: 8 servings
Course: Side Dish
Cuisine: American, French
Calories: 410
Ingredients Method Notes

Ingredients
  

Potatoes
  • 3 lb Yukon Gold potatoes peeled, sliced 1/8 inch thick
Cream Sauce
  • 4 tbsp butter
  • 1 small onion finely diced
  • 3 cloves garlic minced
  • 3 tbsp all purpose flour
  • 2 cups whole milk warm
  • 1 cup heavy cream
  • 1 tsp fresh thyme leaves
  • 1 1/2 tsp salt
  • 1/2 tsp black pepper
  • 1 pinch nutmeg
Cheese
  • 2 cups Gruyère cheese shredded, divided
  • 1 cup sharp cheddar shredded, divided
  • 1/2 cup Parmesan cheese grated

Method
 

  1. Preheat the oven to 375°F and butter a 9x13 baking dish. Slice the potatoes 1/8 inch thick.
  2. Melt the butter, cook the onion 3 to 4 minutes, add the garlic, then whisk in the flour for 1 minute.
  3. Slowly whisk in the milk and cream, add the thyme, salt, pepper and nutmeg and simmer 3 to 5 minutes. Stir in half the Gruyère and cheddar.
  4. Layer the potatoes and sauce in thirds, then top with the remaining cheeses and Parmesan.
  5. Cover and bake 45 minutes, then uncover and bake 25 to 35 minutes until tender and golden.
  6. Rest 15 minutes before serving.

Notes

Assemble up to 24 hours ahead. Leftovers keep 4 days in the fridge.