Prep Time:
25 mins
Cook Time:
35 mins
Total Time:
1 hr
Servings:
6
Ingredients
Directions
Preheat the oven to 400 degrees F (200 degrees C).
Melt butter in a large frying pan over medium heat. Add leeks and celery root and cook for 10 minutes. Add mushroom pieces, 1/2 of the tarragon, and 1/2 of the chives; continue cooking until mushrooms release their liquid, about 6 minutes more.
Meanwhile, combine bread crumbs and Gruyère cheese in a mixing bowl.
Sprinkle flour over the mushroom mixture and stir until absorbed, about 1 minute. Pour in heavy cream slowly while stirring until sauce thickens and turns evenly creamy, about 3 minutes. Add half of the bread crumb–cheese mixture to the pan and stir until the cheese begins to melt, about 2 minutes.
Remove from heat and transfer mixture to a greased baking dish. Top with remaining tarragon, chives, and the rest of the bread crumb mixture. Drizzle with a small amount of water to moisten.
Bake in the preheated oven until the cheese is bubbly, about 10 minutes. Serve immediately.
Cook’s Note
You can use chicken broth to moisten instead of water. If you prefer a crispier top, broil the gratin for 1 to 2 minutes at the end.
Nutrition Facts (per serving)
| 431 | Calories |
| 26g | Fat |
| 43g | Carbs |
| 16g | Protein |
