Mutton HotPot

The Hot Pot has that reputation of "let's just throw everything in" but there's so much more than that, always use great quality ingredients, or at least the best you can, I'm using mutton,
A, because I love mutton
and B, because I believe it will give you the best tasting hot pot,
I'd much rather use Winter lamb or great mutton for my hot pot, I'm also going to put Kidneys into my hot pot, they'll be perfectionists out there who'll be screaming out loud at reading this, but I love kidneys and I think they add a great flavour too
SHOPPING LIST
This will serve 4 people
About 1kg of middle neck mutton
4 kidneys cut into quarters and remove the White core
50g of butter
1 large onion roughly chopped
1kg of potatoes
A couple of bay leaves
50g of well seasoned flour
4 carrots, peeled and cut in half
4 anchovies (optional, but really worth adding)
Good splash of Worcestershire sauce
500ml of lamb stock
METHOD
Melt the butter in a pan and cook the onion till soft, but don't colour
Peel the potatoes and slice thinly
Mix the onions with half the sliced potatoes