Melt the butter in a saucepan over low heat.

Whisk the all-purpose flour into the melted butter and cook over low heat until it smells lightly like cookies.

Gradually whisk in the milk until the béchamel is smooth and thickened.

Season the béchamel with ground nutmeg, salt, and black pepper; set it aside.

Slice each chicken breast horizontally in a butterfly cut, leaving one edge attached.

Cover the chicken with plastic wrap and pound it lightly into an even thin layer.

Season both flattened chicken breasts with paprika, salt, and black pepper.

Layer 2 slices of cooked ham and 2 slices of sliced cheese over each chicken breast.

Roll each filled chicken breast tightly from the short side to enclose the filling.

Wrap the chicken rolls tightly in plastic wrap and freeze them for at least 30 minutes.

Place the all-purpose flour, beaten egg, and breadcrumbs in three separate shallow bowls.

Unwrap each chilled chicken roll and coat it first in all-purpose flour, then in egg.

Press each chicken roll into the breadcrumbs until fully coated.

Preheat the oven to 180°C (350°F).

Heat the vegetable oil in a frying pan over medium-high heat.

Sear the breaded chicken rolls on all sides until golden brown.

Transfer the seared chicken rolls to a baking dish and bake at 180°C (350°F) for 20 minutes.

Check that the chicken reaches 74°C (165°F) at its thickest point, then rest it for 5 minutes.

Chop the bacon and fresh parsley into small pieces.

Slice the chicken rolls and serve them with béchamel, chopped bacon, and fresh parsley.