A cheesy casserole that lets the host savor holiday mornings

By Melissa Clark, The New York Times

It’s not a big deal making eggs and toast to feed one or two. It’s when you try it for a crowd that things start to get tricky. The eggs or the toast always wind up cold, which is bad enough on a weekday, and even worse on a holiday morning.

But turn those ingredients into a breakfast casserole and something magical ensues.

Instead of remaining separate, the bread soaks up the egg, becoming custardy in the center, and puffed and golden on top after baking. You can stir in all kinds of other ingredients to fancy it up — any combination of bacon, sausage, cheeses, herbs or vegetables will heighten its appeal.

Best of all, not only can all of this be done in advance, it should be.

Assembling the casserole the day before allows the bread to soften and absorb the egg mixture as it sits. Then, the next day, all you need to do is pop it in the oven, leaving the cook plenty of time for other morning pursuits — going for a run or taking a shower (or both), caffeinating, even opening presents while the casserole slowly bakes until burnished.

Although many breakfast casseroles lean on bacon and sausage for character and heft, this one is meatless and bright. It’s filled with leeks and spinach sautéed until wilted, the pan deglazed with winy vermouth for extra zip. Then, the vegetables are mixed into a simple egg and milk custard that’s gently suffused with nutmeg, lemon zest and a pinch of cayenne.

I also threw in some cheese, choosing Gruyere for its rich nuttiness, along with some Parmesan for pungency and depth. But you can substitute cheddar, Gouda, manchego, blue cheese, even soft goat cheese, which would make the center of the casserole even creamier and tangier.

And should someone at your table miss the bacon, you can lay some slices on a sheet pan and cook them in the same oven alongside the casserole. This way, the casserole stays vegetarian while the bacon stays crisp, rather than softening into the puddinglike center of the casserole.

Add a beverage or two (coffee, tea, mimosas), and you’ll be all set to serve a savory, festive and highly convenient meal no matter how early your guests are set to arrive.

Recipe: Spinach and Gruyère Breakfast Casserole

By Melissa Clark

Filled with sauteed spinach and nutty Gruyere mixed into a nutmeg and lemon-scented custard, this breakfast casserole is a rich, meatless option for a special occasion breakfast or brunch. Like most of its kind, you can assemble the casserole the day before you want to bake it, then pop it in the oven an hour or so before serving. It will emerge puffed and golden on top, ready for its star turn on any festive table.

Yield: 8 to 10 servings

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

Ingredients

• 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

Preparation

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 a large saute 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. Saute until most of the liquid has evaporated, about 5 minutes longer. Stir in the 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.