Ingredients:
- 3 lbs Yukon Gold potatoes, scrubbed and peeled
- 1 tsp fine sea salt
- 1/2 tsp freshly cracked black pepper
- 4 tbsp unsalted butter
- 1/4 cup all-purpose flour
- 4 cloves garlic, minced
- 2 cups whole milk
- 1 cup heavy cream
- 1 tbsp fresh thyme leaves
- 1/2 cup freshly grated Parmesan cheese
Instructions:
- Peel Yukon Gold potatoes and use a mandoline to slice into uniform 1/8-inch rounds. Submerge in cold water to remove excess starch, then pat completely dry.
- In a heavy-bottomed saucepan, melt butter over medium heat. Whisk in flour and cook for 2 minutes to create a light roux.
- Slowly whisk in the milk and heavy cream. Add minced garlic and thyme. Simmer for 5 minutes until the sauce thickens enough to coat the back of a spoon.
- Grease a 9x13 inch baking dish. Layer one-third of the potatoes in overlapping rows, seasoning with salt and pepper. Pour one-third of the sauce over the layer. Repeat for three layers total.
- Cover with foil and bake at 350°F (175°C) for 45 minutes to steam the potatoes. Remove foil, sprinkle with Parmesan cheese, and bake for an additional 30 minutes at 400°F (200°C) until the top is golden brown and potatoes are tender.