- Crème fraîche and Dijon mustard add lift and brightness so the dish eats creamy, not heavy.
- The gratin delivers fantastic textures: meaty mushrooms and firm, al dente lentils beneath an audibly crisp panko crust.
- You get great versatility with this dish. It’s filling enough to be a main and flawless alongside roasted chicken or seared fish.
Think of this gratin as an embodiment of the best parts of a cozy fall bake — starchy legumes, savory caramelized vegetables, creamy sauce, and crunchy topping — with French green lentils, assorted wild mushrooms, crème fraîche, and oil-coated panko in the starring roles. We suggest a mix of cremini, oyster, shimeji, and shiitake mushrooms, but you can use whatever varieties you like best. Roasting the mushrooms first concentrates their flavor and texture by drawing out some of their moisture, giving them pleasantly chewy edges and deep earthiness that won’t disappear into the sauce. Du Puy lentils (also labeled French green lentils) work beautifully here because they maintain their shape and toothsome texture, even when baked in sauce. A quick swirl of crème fraîche and Dijon mustard brings the filling together, adding creaminess and tang to balance the robust earthy flavors of the mushrooms and lentils.
The topping is a simple combination of panko, olive oil, garlic, and Dijon mustard that’s scattered over the silky lentil-mushroom mixture so that it bakes into a deeply golden, shatteringly crisp crust. Fresh thyme and parsley lend herbaceous lift, and a final sprinkling of thyme echoes the flavor within the gratin.
Serve this straight from the skillet for a casual gathering, completing the meal with warm bread and a crisp green salad dressed with a sharp vinaigrette. Or enjoy it as a side dish to a roast chicken or simply cooked fish. It’s hearty, practical, and dinner party–worthy, all at once. And because all of the components are sturdy, the leftovers reheat like a dream.
What are du Puy lentils, and where can I buy them?
Du Puy lentils, which are also often labeled as French lentils, are smaller than the common brown lentil variety at roughly one-third the size. They’re grayish-green in color, looking a little like capers that have been patted dry. They’re prized for their incredible texture and ability to hold their shape (and not mush out), thanks to their thicker skins. You’ll typically find them at specialty grocers or online sources. In this recipe, you can substitute beluga or black lentils, but avoid brown or red varieties, as they will become overly soft or break down completely during cooking.
Shortcuts to help this dish come together faster
Although this recipe clocks in at under an hour and a half, some folks simply don’t have that much time to devote to dinner. To speed things up, you can substitute two cups of frozen mirepoix for the onion, carrot, and celery to shave off some prep time. Just toss it into the skillet frozen — no need to thaw. And though the flavor won’t quite be the same, in a pinch you can use three to four cups of precooked Puy or black lentils and just a splash of broth instead of cooking the lentils in a quart of broth.
Notes from the Food & Wine Test Kitchen
- For the crispiest, most delicious crust, toss the panko with oil, Dijon mustard, and a touch of garlic so every crumb browns evenly and carries flavor.
- Gently wipe the mushrooms with a damp paper towel to clean them. Avoid submerging them in water, as they’ll absorb too much and won’t brown during roasting.
- Make sure to spread the mushrooms out in a single layer on a large sheet pan for roasting; crowding traps steam and blunts flavor.
Suggested pairing
Try a light-bodied, crisp Beaujolais with this rich vegetarian main, such as Anne-Sophie Dubois Les Cocottes Fleurie.
This recipe was developed by Nicole Hopper; the text was written by Ann Taylor Pittman.
