Ingredients

4 slices white bread (like brioche or sandwich bread)
2 eggs
4 slices cooked ham
1 cup (100g) Gruyère cheese, grated
2 tbsp (30g) butter

For the Mornay Sauce:
2 tbsp (30g) butter
2 tbsp (15g) all-purpose flour
1 cup (240ml) milk
1/2 tsp Dijon mustard
Pinch of nutmeg
Salt and pepper, to taste
1/2 cup (50g) grated Gruyère cheese

Directions

Melt butter, stir in flour, add milk slowly. Whisk until thick. Add mustard, nutmeg, salt, and cheese. Stir until smooth.

In a pan with a little butter, toast bread until golden.

Spread sauce on one slice of bread. Add ham, cheese, and top with the other slice.

Cook in the pan or under a broiler until cheese melts and top is golden.

Cook egg sunny-side-up in a nonstick pan.

Place egg on top of sandwich and enjoy hot.