Risotto is cheap. Mushroom, squash and sage, tomato or chicken if you can stretch to it.
Make sausages into meatballs to have with pasta and the rest of the packet into "burgers" or sausage casserole.
"Lobbies" is a bit of a regional thing but basically cubes of potato, carrot and onion boiled in a pan with an Oxo. When cooked add cubes of corned beef and simmer for a few mins more. Looks awful but tastes good with a bit of HP sauce and bread and butter.
Special fried rice (add egg, prawns, ham or bacon and whatever veg you have). 5 spice lasts forever and makes a big difference to this dish.
Bacon, mashed potato and cabbage.
Bacon and egg pie.
Pork is probably the cheapest meat, Chinese style pork chops with fried rice and broccoli is a fav here. Or chops dipped in breadcrumbs and baked, with potatoes and veg.
Tinned mackerel or sardines on toast or made into fish cakes to have with tinned beans.
Quiche.
Scones and flapjacks for treats.