Re using up, my mother used to make what she called 'dustbin' soup when she was very broke - basically anything soup-able that she had - inc. the odd sad old up carrot, the last dried up rasher of bacon, any leftover mash or other veggies, a bit of rice or whatever. But the soups were always v tasty, and when dh and I were exceedingly broke many years ago I resurrected the dustbin soups - we were in a country where the only cheap thing was the local veggies - and we practically lived on those soups for quite a while.
I still make them with whatever I happen to have, esp. in winter, and they are one of Dh's favourites - he'd eat it every night.
When dds were young I once made a 'dustbin' out of a load of veggies plus pasta and heaven knows what, for dds and friends who'd been out sledging in the snow. Dds told them it was 'dustbin' soup! One of the friends had a Spanish mother and a German father, and she asked me a few days later if I could give her mother the recipe for my 'garbage' soup since she'd enjoyed it so much!
Had to tell her there never was a recipe, different every time.