Parmesan-Crusted Au Gratin Potatoes and Onion

Ingredients and Weight:

• Potatoes, starchy (Russet, Yukon Gold), 3 lbs (1.4 kg)
• Yellow onion, 1 large (1 lb / 450 g)
• Heavy cream, 3 cups (720 ml)
• Whole milk, 2 cups (480 ml)
• Gruyere cheese, shredded, 2 cups (280 g)
• Parmesan cheese, grated, 1 cup (110 g)
• Salt and pepper to taste
• Fresh thyme leaves, for garnish (optional)

Preparation Time:

30 minutes

Cooking Time:

90 minutes (75 minutes baking, 15 minutes browning)

Difficulty Level:

3 (Moderate)

Preparation Method Steps:

1. Preheat oven to 400°F (200°C).
2. Peel and thinly slice the potatoes using a mandoline or sharp knife.
3. Thinly slice the onion.
4. Layer half of the potato slices in a greased 9x13 inch baking dish.
5. Sprinkle with half of the onion and half of the Gruyere cheese.
6. Repeat layer with remaining potatoes, onions, and Gruyere.
7. In a large bowl, whisk together the heavy cream, whole milk, salt, and pepper.
8. Pour the cream mixture over the potatoes.
9. Cover with aluminum foil and bake for 60 minutes.
10. Sprinkle with Parmesan cheese.
11. Remove foil and bake for 15 minutes more, or until the cheese is golden brown and bubbly.
12. Let cool for 10 minutes before serving.

Nutritional Information:

Per serving (1/8 of recipe):

• Calories: 370
• Fat: 22 g
• Protein: 20 g
• Carbohydrates: 32 g
• Sodium: 550 mg

Dish Characteristics:

• Rich and creamy with a crispy Parmesan crust
• Comforting and flavorful
• Perfect for a special occasion or weekend meal

User Comments:

• "These potatoes were absolutely delicious! The perfect combination of cheesy, creamy, and crispy."
• "I love that the Parmesan crust adds a bit of a twist to the classic au gratin recipe."
• "The onions add a nice sweet and savory flavor to the dish."
• "Easy to make and always a crowd-pleaser."
• "I've tried many au gratin recipes, but this one is by far the best."

Special Precautions and Tips:

• Use a starchy potato variety for best results.
• Slice the potatoes thinly and evenly to ensure even cooking.
• Don't overcook the potatoes or they will become mushy.
• Let the potatoes cool for a few minutes before serving to prevent them from breaking apart.
• Garnish with fresh thyme leaves for a touch of elegance.