Zucchini Gratin
Buttery, cheesy and topped with crispy bread crumbs, this zucchini gratin is the ultimate comfort food and makes a fantastic side dish for a Mother’s Day meal. The recipe is published in the cookbook Southern Get-Togethers by Top Chef winner Kelsey Barnard Clark, who loves to serve the dish alongside her Hot Honey Chicken. Best of all, you can prepare the gratin completely in advance, leaving you more time to spend with your guests.
Ingredients
- 4 zucchini, about 2 lb. (910 g) total, thinly sliced
- Kosher salt and freshly ground black pepper
- 12 Tbs. (1 1/2 sticks) (6 oz./165 g) unsalted butter
- 3 onions, thinly sliced
- 1/4 tsp. freshly grated nutmeg
- 2 Tbs. mushroom powder
- 2 Tbs. all-purpose flour
- 1 cup (8 fl. oz./240 ml) cream of mushroom soup
- 2 cups (5 oz./160 g) grated aged Gouda or Parmesan cheese
- 1 bunch green onions, white and green portions, chopped
- 1 bunch fresh flat-leaf parsley, leaves chopped
- 1/2 cup (1 oz./26 g) chopped fresh tarragon
- 1/4 cup (1/4 oz./5 g) chiffonade fresh basil
- 1 cup (2 oz./60 g) panko
- 1 cup (3 3/4 oz./115 g) grated Gruyère cheese
- Pinch of red pepper flakes
Directions
Preheat an oven to 400°F (200°C). Butter an 8-by-10-inch (20-by-25-cm) baking dish.
In a large bowl, toss the zucchini with 2 Tbs. salt, then let stand until the zucchini has started to release its liquid, about 30 minutes. Drain and set aside.
In a large fry pan over medium heat, melt 8 Tbs. (4 oz./110 g) of the butter. Add the onions and cook until golden brown, about 20 minutes. Add the zucchini and cook for 10 minutes. Add 8 to 10 grindings of black pepper, the nutmeg and mushroom powder, then sprinkle with the flour. Add the cream of mushroom soup, adjust the heat to a simmer and cook until the liquid thickens into a sauce, 3 to 5 minutes. Stir in the Gouda, green onions, parsley, tarragon and basil, then pour the mixture into the prepared baking dish.
In a small saucepan, melt the remaining 4 Tbs. (2 oz./55 g) butter. Add the panko, Gruyère and red pepper flakes and stir to combine. Spoon the panko mixture over the zucchini mixture. Bake until bubbly and golden brown on top, about 20 minutes. Let cool for 10 to 15 minutes before serving. Enjoy warm or at room temperature, or cover tightly with aluminum foil or plastic wrap and refrigerate for up to 3 days. Reheat in a 400°F (200°C) oven for 15 to 20 minutes. Serves 4 to 6.
Note: This dish is an easy one to make ahead. After spooning the panko mixture over the zucchini mixture, cover tightly with aluminum foil or plastic wrap and refrigerate for up to 3 days or freeze for up to 3 months. Thaw, if frozen, and let come to room temperature before baking.
Adapted from Southern Get-Togethers by Kelsey Barnard Clark (Chronicle Books, 2024)