Preheat the oven to 180°C fan (356°F fan).

Combine the panko breadcrumbs with the olive oil until all crumbs are evenly moistened.

Toast the oiled panko breadcrumbs in a dry frying pan over medium-high heat until golden, stirring frequently.

Transfer the toasted panko breadcrumbs to a bowl and let them cool while preparing the chicken.

Roll one ham slice around two Edam cheese slices to make a tight filling roll; repeat with the remaining ham and cheese.

Cut a deep pocket into the side of each chicken breast without slicing all the way through.

Insert one ham-and-cheese roll into each chicken breast pocket.

Secure each stuffed chicken breast pocket with 2 to 3 toothpicks.

Place the stuffed chicken breasts bottom-side up on the baking tray and season them with half of the salt, black pepper, and paprika.

Mix the mayonnaise and Dijon mustard in a small bowl until smooth.

Brush half of the mayonnaise-mustard mixture generously over the upward-facing chicken surfaces.

Press half of the cooled toasted panko breadcrumbs firmly onto the coated chicken surfaces.

Turn the chicken breasts over and season the second side with the remaining salt, black pepper, and paprika.

Brush the remaining mayonnaise-mustard mixture over the second side of the chicken.

Press the remaining toasted panko breadcrumbs onto the second side to coat the chicken completely.

Bake the breaded stuffed chicken breasts for 35 to 40 minutes, until the thickest part reaches 74°C (165°F).

Rest the baked chicken for 10 minutes before removing the toothpicks.

Slice the chicken cordon bleu and serve hot, optionally with a crunchy salad.