Open the oysters and place them in a bowl. Remember to check their smell and freshness and remove any shell pieces before putting them in the bowl.
Heat the chicken broth in a pot. Transfer it to a food processor and add 4 oysters with their juice, crème fraiche, parsley and spinach. Mix until you get a nice smooth green soup (save a little of the parsley for the toast).
Sift the soup and add a little salt, pepper and vinegar to taste before serving.
Toast the bread slices in a warm frying pan. Chop the shallot and parsley finely, fold in a little rapeweed oil, apple vinegar, salt and pepper.
Finally cut the 8 remaining oysters into smaller pieces and toss them into the salad. Place this on the warm slices of toast.
Heat the soup up without boiling it and eat with the warm slices of oyster toast.