This simple gratin gets its protein from the lentils and its richness from the tangy creme fraiche and feta cheese. Make your own lentils, use leftovers or buy cooked lentils in vacuum-sealed bags or cans.

Until recently, most of my cooking experience with lentils involved the large green ones cooked in a pot with diced onion and chunks of carrot. I would whip up a batch when I wanted an inexpensive, quick-to-make pot of filling food that I could eat for a few days.

In 2020, I developed a deeper appreciation for the rich variety of the legume and the myriad ways you can cook with them thanks to the variety of recipes we have tested and published here at The Washington Post.

This week, I’m sharing a simple gratin featuring one of my now-favorites, the French lentil, which is a variety of green lentil, but smaller and darker. I like them because after cooking they remain a bit firm. Also, while still earthy, they have a milder, more subtle flavor.

Because they hold their shape, they look so pretty in dishes like this one, with its pale, crunchy feta and panko topping that when scooped out reveals the dark legumes beneath.

You can buy precooked, vacuum-packed lentils online and at some specialty stores, but they may be hard to find in most groceries. One of the things that makes lentils so easy to incorporate into weeknight cooking, however, is that they cook so quickly. To make 2 1/2 cups of cooked French lentils for this dish, add a couple of cups of water or broth to a pot with a little salt. Add one cup of lentils and bring it to a boil. Then, reduce the heat to low and simmer until the lentils are just tender, about 20 minutes.

This gratin is a great way to use up leftover lentils as well.

And, while one lentil cannot always be substituted for another due to their texture and flavors, in this case, if you can’t find French lentils, you can make the dish with the more common green or brown lentils, which also are more readily available precooked in cans. The bigger green lentils will make the dish a bit heavier and mushier, but the flavor combinations still work.

Also, if you don’t have creme fraiche, you can use a cup of sour cream in its place.

Leek and French Lentil Gratin With Feta

Active time: 15 minutes | Total time: 40 minute

4 to 6 servings

Storage Notes: Leftovers can be refrigerated for up to 3 days. Reheat for about 10 minutes in a preheated 350-degree oven.

Ingredients

2 tablespoons unsalted butter

3 cloves garlic, minced or finely grated

1 pound leeks, white and light green parts only, washed well and thinly sliced

2 teaspoons fine sea salt, divided

1 teaspoon freshly ground black pepper

2 1/2 cups cooked French lentils (see NOTE)

1 1/4 cups (10 ounces) crème fraîche (may substitute a generous 1 cup of full- or low-fat sour cream)

5 ounces feta cheese, crumbled

3/4 cup (1 3/4 ounces) panko

1 tablespoon olive oil

Steps

Position a rack in the middle of the oven and preheat to 400 degrees.

In a 6-cup gratin or baking dish, combine the butter and garlic and place in the oven to melt. (If you haven’t already, wash and slice the leeks while the butter melts.) Add the leeks to the butter mixture, sprinkle with the salt and pepper and toss to combine. Return the dish to the oven and roast for 20 minutes, or until wilted and softened.

In a medium bowl, combine the lentils and creme fraiche. Spread the lentil mixture evenly over the leeks. Sprinkle the feta over the lentils, followed by the panko, and drizzle with the olive oil. Bake for 15 minutes, or until just golden on top.

Serve hot.

NOTE: To make 2 1/2 cups of cooked French lentils, in a medium saucepan over high heat, combine 2 cups of water or chicken broth, 1 cup (6 1/2 ounces) of rinsed, dried lentils and 1 teaspoon of salt. Stir and bring to a boil. Reduce the heat to low and simmer until the lentils are just tender, 20 to 25 minutes.

Nutrition | Calories: 322; Total Fat: 15 g; Saturated Fat: 8 g; Cholesterol: 41 mg; Sodium: 710 mg; Carbohydrates: 36 g; Dietary Fiber: 8 g; Sugar: 7 g; Protein: 13 g.