This make-ahead breakfast casserole is a perfect company dish. Served for brunch or a casual supper, it’s an ingenious way to use up what’s on hand. Grand Central founder Gwenyth Bassetti likes to make it with spinach, mushrooms and mozzarella, but you may use any cheese you like (Gruyere is particularly nice) and, if it suits you, add extra veggies and/or browned sausage or crumbled bacon to taste. The one essential is good artisan bread (we suggest Como or Sourdough loaf).
Makes 8 servings
6 tablespoons (¾ stick) unsalted butter, divided
½ cup chopped onion
2 cups (4 ounces) thinly sliced button or cremini mushrooms
2 bunches (about 2 pounds) fresh spinach, stemmed, blanched and coarsely chopped, or 1 10-ounce package frozen chopped spinach, thawed and squeezed
2 tablespoons chopped fresh basil or 1 teaspoon dried
Salt and freshly ground black pepper, to taste
4 cups half-and-half or milk, or a combination
1 loaf sturdy bread (such as Como or Sourdough), heavy crusts removed and thinly sliced
1 ½ cups shredded mozzarella cheese, divided
½ cup grated Parmesan cheese, divided
Melt 2 tablespoons butter in large skillet over medium-high heat. Add onion and mushrooms and saute until soft, 4 to 5 minutes. Stir in spinach, basil and salt and pepper to taste. Set aside to cool.
Whisk eggs in large bowl until well mixed. Whisk in half-and-half or milk and season with salt and pepper.
Butter 8½-by-11-inch or 9-by 13-inch baking dish. Cut bread slices to cover bottom, with pieces fitting snugly. Spread vegetable mixture over bread and top with half of mozzarella and Parmesan cheeses (reserve remaining cheese for baking). Arrange a second layer of bread over the cheese, then pour egg mixture over. Press lightly into egg mixture and dot with remaining 4 tablespoons butter. Cover with plastic wrap and weight the top with a heavy plate or slightly smaller pan. Refrigerate for at least 4 hours or overnight.
Preheat oven to 350 degrees. Remove plastic wrap from Strata and sprinkle top with reserved shredded cheese. Place baking dish in a larger roasting pan and fill pan with water halfway up baking dish. Bake until browned on top, filling is set and center puffs up slightly, about 50 to 60 minutes. Let stand 5 minutes before cutting; serve warm or at room temperature.