Name: Rich Potato Gratin Recipe
Prep time: 25 min
Cook time: 50 min
Total time: 1 h 15 min
Cuisine: French
Ingredients: 3 tbsp all-purpose flour (or gluten-free flour); 1 1/2 cups milk (or heavy cream for extra richness); 1/2 cup shredded gruyere cheese, freshly grated; 1 pinch ground nutmeg (optional); 1 tsp fresh thyme, chopped (or 1/2 tsp dried thyme); 3 tbsp unsalted butter (preferably Kerrygold); 1 small onion, minced (about 1/4-inch pieces); 1 garlic clove, grated or freshly minced; Salt and black pepper, to taste; 4 lb potatoes, sliced thin (about 1/8-inch thickness); 1 cup shredded gruyere cheese, freshly grated for topping

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Introduction

Rich Potato Gratin is a classic comfort dish that combines thinly sliced potatoes with a creamy, cheesy sauce for a luscious and satisfying side. This recipe uses gruyere cheese and fresh thyme to add depth and a touch of elegance to a beloved favorite.

The image shows a white rectangular baking dish filled with golden brown scalloped potatoes arranged in even overlapping layers. Each potato slice is coated with a creamy sauce that has a smooth texture and bubbly, browned cheese on top. The top layer has crispy browned spots and is sprinkled with cracked black pepper and a few fresh green thyme sprigs as garnish. The dish rests on a white marbled surface with a dark cloth partially visible beneath it. photo taken with an iphone --ar 4:5 --v 7

Ingredients

3 tbsp flour (all-purpose or gluten-free)
1 1/2 cups milk (or heavy cream for extra richness)
1/2 cup shredded gruyere cheese (freshly grated if possible)
1 pinch ground nutmeg (optional but recommended)
1 tsp fresh thyme, chopped (or 1/2 tsp dried)
3 tbsp butter (unsalted recommended)
1 small onion, minced (about 1/4-inch pieces)
1 garlic clove, grated (freshly minced preferred)
Salt and black pepper, to taste
1 cup shredded gruyere cheese (for layering and topping)
4 lb potatoes, sliced thin (about 1/8-inch thickness)

Instructions

Step 1: Preheat your oven to 350°F. Prepare all ingredients by slicing the potatoes into thin 1/8-inch rounds using a mandoline or slicing blade for even cooking. Mince the onion, grate the garlic, chop the thyme, and grate the gruyere cheese to have everything ready.
Step 2: Melt the butter over medium heat in a saucepan. Add the minced onion, grated garlic, and thyme, sautéing gently for 3-5 minutes until the onion becomes soft and translucent without browning.
Step 3: Sprinkle the flour over the aromatic mixture and cook for 1 minute, stirring constantly to create a roux. Slowly whisk in the milk, continuing to whisk for 1-2 minutes until the sauce thickens and coats the back of a spoon. Remove from heat and stir in the 1/2 cup gruyere cheese, nutmeg, salt, and pepper until smooth and creamy.
Step 4: Butter a baking dish and pour a thin layer of the cream sauce on the bottom. Arrange half of the sliced potatoes in an overlapping pattern, then pour half of the remaining sauce over them. Add the rest of the potatoes in another layer and top with the remaining sauce, ensuring all gaps are filled.
Step 5: Sprinkle the remaining 1 cup of shredded gruyere evenly over the top. Bake for 45-60 minutes until the potatoes are tender and the top is golden brown. For a deeper crust, broil for the last 2-3 minutes, watching carefully. Let the gratin rest for 10 minutes before serving.

Tips & Variations

Use heavy cream instead of milk for an even richer sauce and creamier texture.
Freshly grated gruyere melts better and adds a more pronounced flavor than pre-shredded cheese.
Try adding a sprinkle of fresh parsley or chives on top just before serving for a burst of color and freshness.
For a gluten-free version, substitute the all-purpose flour with a gluten-free flour blend.
To avoid browning if preparing in advance, cover tightly with plastic wrap and refrigerate before baking.

Storage

Store leftover gratin in an airtight container in the refrigerator for up to 3 days. Reheat portions in the oven at 350°F until warmed through to maintain the creamy texture and crispy top. Avoid microwaving to preserve texture.

How to Serve

A close-up image of a white rectangular baking dish filled with layers of thinly sliced golden-yellow potatoes arranged vertically and slightly overlapping in several even rows, covered with a creamy white sauce that has browned and bubbled at the edges and on top of the potato slices, showing textured patches of melted cheese with a golden-brown crust. Small sprigs of fresh green herbs are scattered on top, adding a touch of color and freshness to the creamy, cheesy potato layers. The baking dish is placed on a white marbled surface with a dark blue cloth partially visible in the background. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I prepare the gratin the night before?

Yes, you can assemble the gratin the night before and refrigerate it covered. Bring it to room temperature before baking to ensure even cooking. The cream sauce helps prevent the potatoes from browning during this time.

What potatoes work best for gratin?

Starchy potatoes like Russets or all-purpose varieties such as Yukon Golds are ideal. They soften well during baking and absorb the creamy sauce perfectly without becoming mushy.