Potato Leek Gratin

5 from 3 votes

Potato Leek Gratin is a delightful side dish with slices of potato and leeks in a creamy sauce, topped with shredded gouda and grated Parmesan.

Prep Time10

Cook Time1

Total Time1 10

Course: Side Dish

Cuisine: American, French

Keyword: leek potato gratin, potato and leek gratin, potato leek gratin

Servings: servings

Calories: 454kcal

Preheat the oven to 425 degrees Fahrenheit.
In a small pot, add the heavy cream along with thyme, garlic, nutmeg and salt and pepper. Bring the cream to a gentle simmer to warm through, for about 5-7 minutes.
Meanwhile, place a medium sized skillet over medium heat and drizzle with olive oil. Add the sliced leeks and sauté until the leeks are soft but not browned, for about 10-12 minutes. Once done, set the skillet aside.
Grease a medium sized 8 x 10 inch casserole dish with 1 tablespoon of softened butter, all around the bottom and sides of the dish.
Transfer half pf the sautéed leeks to the bottom of the casserole dish, then stack the sliced potatoes on top and then layer the other half of the sautéed leeks on top.
Remove the thyme and garlic from the cream mixture and gently pour the warm cream around the sliced potatoes.
Top the gratin with shredded gouda, Parmesan cheese and fresh thyme.
Place the gratin on a small baking sheet, just in case it spills over and place in the oven for 45-50 minutes, until the potatoes are tender and cream has thickened.
If the top doesn't brown as much as you like, place potato gratin under the broiler for 3-5 minutes.

- Use the Right Potatoes: Opt for starchy potatoes, such as Russet or Yukon Gold, as they hold up well during baking and become wonderfully creamy.

- Slicing Uniformly: Use a mandoline slicer or a sharp knife to ensure that your potatoes have consistent thickness and cooks evenly.

- Prep Leeks Ahead: Leeks freeze very well and I often prep a bunch ahead of time when I want to make vichyssoise. To prep leeks, slice them thin and submerge in water to remover any dirt stuck between the layers. Then remove and dry the sliced leeks and place them in a resealable plastic bag in the freezer.
- Broil the Top: If the top isn't brown enough while baking, place it under the broiler for a few minutes. But keep a close eye on it, so it doesn't burn too quickly.