Spread the slices of bread with the honey mustard. Place the Gruyère and Camembert on half of the slices, top with the remaining slices and press down gently. Brush both sides of the sandwiches with oil.
To grill the sandwiches
Charcoal/gas/electric grill: Cover the sandwiches and grill over/on a medium heat (approx. 200 °C for approx. 2 mins. on each side.