Easy Lamb Hotpot - All-in-one Dish

There are several methods of making this dish, the recipe I've given below is pretty straightforward, as you just layer everything into your casserole - without precooking anything.  However, you can cook the lamb stew in advance, and add sliced par-boiled potatoes on top afterwards and brown them in the oven - as per Jamie Oliver's version:

Ingredients: enough for 2 or 3 (or 4 smaller portions)
approx. 1lb. lamb steaks - trimmed and cut into bite-size pieces - (you can use any other suitable cuts)
1 large courgette
1 stick or 2 of celery
1 large tomato
3 or 4 potatoes
1 onion
1 large carrot
couple of garlic cloves - peeled and chopped
Try and cut the vegetables into approx. the same size chunks
handful of barley - if wanted
dried oregano, fresh rosemary (if poss)
salt and pepper
flour

Lay the vegetables, except the potato and onion, on the bottom of your casserole.
Dredge a little flour over the top, some salt and pepper and the herbs.
You could also throw in a handful of barley - which is lovely with lamb.
Toss the lamb pieces in seasoned flour and place on top.
Add the potatoes and onions.
Pour hot water or stock over the top to just about cover - a little less is fine.
Season the top layer of veg.

I cover the casserole with a layer of either greaseproof or cooking parchment, then a cover of double-foil.  (A lid is fine :) )

Oven: 
1. about an hour at 190 deg.C
2. turn the oven temperature down a little and cook for another hour or so,
3. then you can just leave it in the oven at about 100 deg.C until you want it.  The longer it cooks - it's just fine.

If you find the gravy hasn't come out thickly enough for you - just carefully strain it off, add some slaked arrowroot or cornstarch and reheat it separately in a small saucepan - this should thicken it up to your taste.  Pour it back over the casserole.