Croque Madame Casserole with Ham and Gruyère

Ingredients for Croque Madame Casserole with Ham and Gruyère

• 12 (3/4"-thick) slices day-old white bread, such as Pullman, pain de mie, or country bread (a square-shaped loaf works best)

• 6 tablespoons unsalted butter

• 3 tablespoons plain flour

• 725ml whole milk

• 1/4 teaspoons freshly grated or ground nutmeg

• 1 1/4 teaspoons kosher salt, divided

• 1/2 teaspoons freshly ground black pepper, divided

• 500g grated Gruyère (about 275g ), divided

• 60ml Dijon mustard

• 12 thin slices Black Forest ham (about 275g )

• 6 large eggs

• Nonstick vegetable oil spray

Arrange racks in top and middle of oven; preheat to 191°C. If bread is not a day old or still feels moist, arrange slices in a single layer on a baking sheet and bake, flipping once, until dry to the touch but not toasted, 5–10 minutes. Using a 2" ring or biscuit cutter or sharp paring knife, cut a hole in the centre of 6 bread slices. Trim bread to fit in 2 even layers in a 13x9" baking dish, with the whole slices on the bottom and the slices with holes on the top, forming 6 sandwiches. Remove from dish.

Melt butter in a medium pot over medium heat. Add flour and cook, whisking constantly, until butter foams then subsides (make sure it doesn't brown), and mixture is light gold and thickened, about 3 minutes. Slowly add milk, whisking constantly to prevent lumps from forming. Increase heat to medium-high and cook, whisking, until mixture thickens and coats the back of a spoon, 4–6 minutes. Reduce heat to very low. Whisk in nutmeg, 3/4 teaspoons salt, and 1/4 teaspoons pepper into the Béchamel sauce. Whisk in 240ml Gruyère a handful at a time, making sure cheese is melted before adding more. (Béchamel with cheese added is technically called a Mornay sauce.) You should have about 850ml sauce.

Spread one-third of the Béchamel in the dish. Arrange 6 whole slices of bread in a single layer in dish. Spread Dijon evenly on bread. Top each with 2 slices of ham, folding to fit on bread if necessary.

Spread another third of the Béchamel over ham. Sprinkle evenly with 240ml Gruyère. Place 6 bread slices with holes on top to form 6 sandwiches. Spread remaining Béchamel over sandwiches; sprinkle with 240ml Gruyère (avoid holes to save room for eggs).

Crack 1 egg into each hole. Sprinkle with remaining 40g Gruyère. Season with remaining 1/2 teaspoons salt and 1/4 teaspoons pepper.

Spray a large piece of foil with nonstick spray. Place foil, oiled side down, over baking dish, crimping to seal. Bake on middle rack for 20 minutes. Remove foil, increase oven temperature to 204°C, transfer dish to top rack, and bake until egg whites are just barely set and yolks are still runny (eggs will continue to cook slightly when removed from oven), 8–12 minutes. Let cool 10 minutes before serving.

Disclaimer

While every effort has been made to ensure the information is accurate and up to date, individual needs may vary and dietary requirements can differ based on personal health conditions. Always check food labels and allergen information before preparing or consuming any recipe. If you have specific health concerns, allergies, intolerances, or are following a medically prescribed diet, seek advice from your GP, pharmacist, or a registered dietitian before making significant changes to your diet or lifestyle.