Rich Potato Gratin Recipe

Introduction

This Rich Potato Gratin is a creamy, cheesy dish that’s perfect as a comforting side or a hearty main. Thinly sliced potatoes are layered with a flavorful béchamel sauce and melted gruyere cheese for a golden, bubbling finish.

Ingredients

• 3 tbsp butter
• 1 small onion, minced
• 1 garlic clove, grated
• 1 tsp fresh thyme, chopped or 1/2 tsp dried thyme
• 3 tbsp flour (use gluten-free if desired)
• 1 1/2 cups milk or substitute heavy cream
• 1/2 cup shredded gruyere cheese
• 1 pinch ground nutmeg (optional)
• Salt and black pepper, to taste
• 4 lb potatoes, sliced thin
• 1 cup shredded gruyere cheese

Instructions

1. Step 1: Preheat your oven to 350°F. Slice the potatoes into thin 1/8-inch rounds using a mandoline or box grater blade for even cooking. Mince the onion, grate the garlic, chop the fresh thyme, and shred the gruyere cheese. Prepare all ingredients before starting the sauce.
2. Step 2: Melt the butter over medium heat in a saucepan. Add the minced onion, grated garlic, and thyme. Sauté gently for 3-5 minutes until the onion softens and becomes translucent, avoiding browning.
3. Step 3: Sprinkle the flour over the aromatic mixture, stirring constantly for 1 minute to form a roux. Gradually whisk in the milk, stirring vigorously to prevent lumps. Continue whisking for 1-2 minutes until the sauce thickens and coats the back of a spoon. Remove from heat and stir in 1/2 cup gruyere cheese, nutmeg, salt, and pepper until smooth and creamy.
4. Step 4: Butter a baking dish and pour a thin layer of the cream sauce onto the bottom. Arrange half the sliced potatoes in overlapping layers over the sauce, then pour half of the remaining sauce on top. Repeat with the remaining potatoes and sauce, filling any gaps for even cooking.
5. Step 5: Sprinkle the remaining 1 cup of shredded gruyere cheese evenly over the top. Bake at 350°F for 45-60 minutes until potatoes are tender and the top is lightly golden. For a deeper crust, broil for 2-3 minutes, watching carefully. Let rest for 10 minutes before serving.

Tips & Variations

• Use a mandoline to slice potatoes evenly for consistent cooking and texture.
• Substitute the gruyere with cheddar or fontina for different flavors.
• For extra richness, replace milk with heavy cream or half-and-half.
• Add a sprinkle of breadcrumbs on top before baking for a crunchy crust.
• Include cooked pancetta or sautéed mushrooms between layers for added depth.

Storage

Store leftover gratin in an airtight container in the refrigerator for up to 3 days. Reheat gently in a 350°F oven covered with foil until warmed through, about 15-20 minutes. Avoid microwaving to preserve the creamy texture.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I prepare the gratin in advance?

Yes, you can assemble the gratin and refrigerate it unbaked for up to 24 hours. Allow it to come to room temperature before baking to ensure even cooking.

What type of potatoes work best for gratin?

Starchy or all-purpose potatoes like Russets or Yukon Gold are ideal as they become tender and absorb the sauce well without falling apart.

Rich Potato Gratin Recipe

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This Rich Potato Gratin is a classic French-inspired dish featuring thinly sliced potatoes baked in a creamy béchamel sauce infused with garlic, thyme, and Gruyère cheese. The result is a luscious, cheesy potato casserole with a beautifully golden crust, perfect as a comforting side or elegant main course.

• Author: Viktoria
• Prep Time: 25 minutes
• Cook Time: 50 minutes
• Total Time: 1 hour 15 minutes
• Yield: 8 servings 1x
• Category: Side Dish
• Method: Baking
• Cuisine: French
• Diet: Gluten Free

Ingredients

Scale 1x2x3x

For the Aromatic Béchamel Sauce

• 3 tbsp butter
• 1 small onion, minced
• 1 garlic clove, grated
• 1 tsp fresh thyme, chopped or 1/2 tsp dried thyme
• 3 tbsp flour (use gluten-free if desired)
• 1 1/2 cups milk or substitute heavy cream
• 1/2 cup shredded Gruyère cheese
• 1 pinch ground nutmeg (optional)
• Salt and black pepper, to taste

For the Potato Layers

• 4 lb potatoes, sliced thin (about 1/8-inch thick)
• 1 cup shredded Gruyère cheese

Instructions

1. Prepare Mise en Place and Preheat Oven: Preheat your oven to 350°F (175°C). Slice the potatoes into thin 1/8-inch rounds using a mandoline or slicing blade for uniform thickness. Mince the onion, grate the garlic, chop the thyme, and shred the Gruyère cheese. Having all ingredients prepared upfront ensures smooth progress in subsequent steps.
2. Build the Béchamel Base with Aromatics: In a medium saucepan, melt the butter over medium heat. Add the minced onion, grated garlic, and thyme, then sauté gently for 3–5 minutes until the onion is soft and translucent but not browned, allowing the flavors to infuse the butter.
3. Make the Cream Sauce: Sprinkle the flour over the aromatic butter mixture and cook for 1 minute, stirring constantly to create a roux and eliminate raw flour taste. Gradually whisk in the milk, stirring vigorously to avoid lumps. Cook 1–2 minutes until the sauce thickens and coats the back of a spoon. Remove from heat, then stir in 1/2 cup shredded Gruyère, ground nutmeg, salt, and black pepper until the cheese is fully melted and the sauce is smooth and creamy.
4. Layer the Potatoes with Sauce: Butter a baking dish and pour a thin layer of the cream sauce to prevent sticking. Arrange half the sliced potatoes in an overlapping pattern, then pour half of the remaining sauce over them. Add the rest of the potatoes in another overlapping layer and pour the remaining sauce on top, making sure to cover all gaps for even cooking.
5. Bake and Finish the Gratin: Sprinkle 1 cup of shredded Gruyère evenly over the layered potatoes. Bake at 350°F (175°C) for 45–60 minutes until potatoes are tender when pierced and the top is lightly golden brown. For a deeper crust, broil for 2–3 minutes at the end, watching carefully to avoid burning. Let the gratin rest for 10 minutes before serving to allow the layers to set and create a creamy interior.

Notes

• Use a mandoline for consistent potato slices, ensuring even cooking.
• You can substitute heavy cream for milk for a richer sauce.
• Use gluten-free flour to make the recipe gluten free if needed.
• Letting the gratin rest after baking helps to set the layers for easier serving.
• For extra flavor, fresh thyme is preferred but dried thyme works as well.
• Broil carefully to avoid burning the cheesy top crust.

Keywords: Potato Gratin, Scalloped Potatoes, Béchamel Sauce, Gruyère Cheese, French Potato Casserole, Comfort Food, Gluten Free Potato Dish