Make a horizontal incision in each fillet (without going right through).
Open them and flatten them out.
Place them on cling-wrap and season.
Chop up the herbs, and sprinkle them regularly over the meat.
Moisten with olive oil.
Roll up the meat in the cling-wrap and leave it for a while in the fridge.
Grate the Gruyère with a potato grater, sprinkle a thin layer of cheese over a cake tray covered with greaseproof paper.
Bake for about 7 minutes in the oven at 200°C.
Leave to cool, then break the crispy grated cheese into small pieces.
Slice the meat as finely as possible, arrange the slices on a plate and decorate with the crispy Gruyère cheese.
Sprinkle the lemon juice over the meat.