The lamb stew mum made from the leftover roast. She always made a couple of large Yorkshire puddings to put the stew in. Mum was a dab hand at both. I've never been able to replicate the stew.
My mum made a hotpot with left-over roast lamb and as far as I know nothing but onions layered with meat and sliced potatoes and maybe leftover gravy, plus stock. It was wonderfully flavoursome and I have never been able to make one as good... in spite of trying many times. I suspect it has a lot to do with how long it is cooked and I was never able to give it the time it needed. No slow cookers in those days.
I used to love to come home to cheese pie. My mother would mash potatoes and add grated cheese and onion and a knob of butter. Then she would fill a roasting dish with the mixture and lay strips of bacon all over the top. It smelled wonderful when we came in on a cold day. I used the love a corner piece because the edges would be brown and crispy. There was always a large pan of soup on the stove all winter long. It would be different each day. My mother did this almost until the end of her life. We would call in and automatically help ourselves to a ladle of thick winter soup.