Preferably use a heavy, deep oven dish which can be used also over the hob for this recipe. Prick the sausages with a fork and cook in a pot of salted hot water. When ready, remove the sausages from the water and allow to cool down completely. Next, cut the sausage into thick slices. Fry the rabbit pieces in hot oil until browned, and then remove from the pan and take off the heat. Next, lay half of the potato slices in the dish and season with salt and pepper. Top up with half of the sliced onions, garlic, mushrooms, olives, herbs and sausage. Place the browned rabbit pieces on top and cover with the remaining ingredients. Coat the rabbit pieces completely with a neat layer of potatoes. Pour over the chicken stock, season well with salt and pepper, and brush the top of the potatoes with some olive oil. Cook the rabbit in a hot oven at 220°c for approximately an hour, or until the rabbit is completely cooked.