Preheat the oven to 180°C.
Slice potatoes, carrots, onions and celery.
Cover the base of a casserole dish with half the potatoes.
Put the lamb chops on top of the potatoes.
Add salt and pepper to taste.
Mix the herbs with the vegetables.
Spread vegetables over the lamb chops add more salt and pepper.
Arrange the rest of the potatoes over the vegetables.
Overlapping the potatoes slightly.
Brush the melted margarine over potatoes.
Cover and bake for 2 ½ to 3 hours.
Remove the cover a half an hour before the end of cooking time so that the potatoes can brown.
Serve with a salad.