Recipes

Croque Monsieur Casserole

By
Mary Berg

Published: 

Croque Monsieur Casserole
Portions
Serves 8 to 10

Ingredients

For the casserole:

  • 8 store-bought croissants
  • 6 tablespoons Dijon mustard
  • 16 slices deli ham
  • 2 cups grated Gruyère cheese
  • 8 eggs
  • 2 cups milk
  • ¼ teaspoon freshly grated nutmeg
  • Salt & pepper

For the béchamel:

  • 3 cups milk
  • 3 tablespoons butter
  • 3 tablespoons all-purpose flour
  • ½ teaspoon Herbes de Provence
  • Pinch freshly grated nutmeg
  • ½ cup grated Parmigiano Reggiano
  • 1 ½ cups grated Gruyère, divided
  • Salt & pepper

Directions

  1. Grease a 9- by 13-inch baking pan with non-stick cooking spray.
  2. Split the croissants in half lengthwise, leaving a hinge on one side, and spread each with some mustard. Layer two slices of ham into each and stuff each with ¼ cup of cheese. Sandwich the croissants together and cut each in half. Nestle them into the prepared baking pan and set aside.
  3. In a large bowl, whisk together the eggs and milk and season with nutmeg, salt, and pepper. Carefully pour the egg mixture over the croissants and lightly press down to ensure the croissants are evenly saturated. Cover the pan with plastic and refrigerate for at least 4 hours or up to overnight.
  4. When ready to bake, remove the casserole from the fridge and let it sit at room temperature for 30 minutes. Meanwhile, heat the oven to 350ºF and make the béchamel by heating the milk over low or in the microwave. Melt the butter in a medium pot over medium heat. Sprinkle over the flour and whisk to combine. Cook for 30 seconds to toast the flour. While whisking, slowly pour in the warmed milk and season the Herbes de Provence and a pinch of nutmeg. Bring to a simmer and turn the heat down to medium-low, stirring occasionally, until the mixture is thick and will coat the back of a spoon. Once thick, whisk in the Pecorino and ½ cup of Gruyère and season to taste with salt and pepper.
  5. Pour the béchamel over the casserole and scatter with the remaining cup of Gruyère. Bake the casserole for 50 to 60 minutes or until puffed, golden, and the centre is set. Allow the casserole to rest for 5 minutes before serving.