Spinach and Gruyere Breakfast Casserole

This breakfast casserole is a rich, meatless option for a special occasion breakfast or brunch.

Makes: 8 to 10 servings

Total time: 1 hour, 50 minutes, plus at least 8 hours chilling and 10 minutes resting

8 ounces baguette or other crusty bread, cut into 1 1/2-inch cubes

6 tablespoons unsalted butter

1 teaspoon kosher salt, more as needed

2 leeks, trimmed, halved and thinly sliced into half-moons

10 ounces fresh spinach

1/4 teaspoon grated nutmeg

Large pinch of ground cayenne

1 teaspoon finely grated lemon zest

2 tablespoons dry vermouth or white wine

8 large eggs

2 cups half-and-half (or use a mix of milk and heavy cream)

1/2 teaspoon freshly cracked black pepper

4 ounces Gruyere, grated (2 cups)

3/4 cup grated Parmesan

1. Heat oven to 350 degrees. Lightly butter a 9-by-13-inch baking dish or a large gratin dish.

2. Spread baguette cubes on a baking sheet. Bake until crisp, about 8 to 10 minutes. Transfer cubes to a large bowl and toss with 4 tablespoons melted butter and a pinch of salt.

3. Meanwhile, in large sauté pan, melt the remaining 2 tablespoons butter over medium-high heat. Add leeks and a pinch of salt, and sauté until tender and lightly golden, about 5 minutes.

4. Stir in about half of the spinach leaves, a pinch of salt, nutmeg, cayenne and lemon zest, and stir until wilted, about 2 to 4 minutes. Stir in remaining spinach and another pinch of salt. Sauté until most of the liquid has evaporated, about 5 minutes longer. Stir in vermouth and let cook for 2 to 4 minutes, or until the pan looks dry. Taste and add more salt if needed. Let spinach cool.

5. In a medium bowl, whisk together eggs, half-and-half, pepper and 1 teaspoon salt. Add mixture to the baguette, tossing well. Add spinach, 1 3/4 cups Gruyere and 1/2 cup Parmesan, and toss everything until mixed (your hands work well for this).

6. Pour mixture into prepared baking dish, cover and refrigerate for 8 hours or overnight.

7. When ready to bake, heat oven to 350 degrees. Uncover and top casserole with remaining 1/4 cup grated Gruyere and 1/4 cup grated Parmesan. Bake for 50 to 60 minutes, or until the center is set and no longer liquidy (it’s fine if it puffs). Let sit for 10 to 20 minutes before serving.