Many options are available for this type of sandwich. Cream cheese, goat cheese, boursin aux herbes can be used. Pistachio may be replaced with hazelnuts an pine nuts. Other condiments may be added too, such as shallots. Lettuce, romaine, roquette.. and the jambon could be subbed for prosciutto or dry cured duck breast or salami or smoked salmon with lemon zest and juice.
Mix cheese with some cream until you reach desired consistency. Season with salt, pepper and chives.
Slice bread in half and toast with a drizzle of olive oil. Garnish bottom with the cheese filling and add remaining for the top. Add more chives, chopped nuts (toasted in desired) and salad. Garnish the lid with more of the filling and arrange jambon and flip over the base. Enjoy!