Spinach, Mushroom, and Gruyère Strata
 
Makes 6 servings
Ingredients
  • 8 cups 1-inch-cubed French bread
  • 9 large eggs
  • 2 cups whole milk
  • 2 tablespoons Dijon mustard
  • 1 teaspoon kosher salt, divided
  • ½ teaspoon ground black pepper, divided
  • 4 tablespoons unsalted butter
  • 1 tablespoon vegetable oil
  • 1 white onion, diced (about 1 cup)
  • 2 (8-ounce) packages baby portobello mushrooms, coarsely chopped
  • 1 clove garlic, minced
  • 1 (12-ounce) package frozen spinach, thawed and squeezed dry
  • 1 cup freshly grated Parmesan cheese
  • 2 cups shredded Gruyère cheese
Instructions
  1. Preheat oven to 350°.
  2. On a rimmed baking sheet, arrange bread cubes.
  3. Bake until lightly toasted, 2 to 3 minutes.
  4. Spray a 2-quart baking dish with cooking spray.
  5. In the container of a blender, process eggs, milk, mustard, ½ teaspoon salt, and ¼ teaspoon pepper until smooth.
  6. In a large skillet, melt 2 tablespoons butter with oil over medium-high heat. Add onion, and cook, stirring frequently, for 5 minutes. Add mushrooms and remaining 2 tablespoons butter, and cook, stirring occasionally, until soft and slightly golden brown and most of moisture has evaporated, about 8 minutes. Add garlic, and cook, stirring constantly, for 1 minute. Add spinach, and cook, stirring constantly, for 2 minutes. Stir in remaining ½ teaspoon salt and remaining ¼ teaspoon pepper until combined. Remove from heat, and let cool for about 5 minutes. Stir in bread cubes and Parmesan until combined. Spoon into prepared pan. Pour egg mixture on top, and gently press down to soak all pieces of bread. Let stand for 20 minutes, or cover and refrigerate overnight.
  7. Bake, uncovered, until almost set in center, 50 minutes to 1 hour. Sprinkle Gruyère on top, and bake until cheese is melted and golden brown and center is set, 10 to 15 minutes more. Let cool for 5 minutes before serving.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/spinach-mushroom-and-gruyere-strata/