Mix the cream with the vegetable stock, marjoram, pepper, nutmeg and salt. Cut the potatoes into slices and simmer with the seasoned cream for 2 minutes. Fill the potato gratin into 5 small molds. Place in the oven at 160 ° C for 10-12 minutes, then raise the temperature to 170 ° C and cook again for 5-10 minutes.
Meanwhile, place 5 tablespoons of Gruyère on a baking sheet lined with baking paper with as much space as possible and bake into crispy cheese chips. Finally, put these in the finished gratins.