Alison, very like our cheater Hamburger (= mince) Soup my wife makes (she lacks patience too, and seldom thinks about dinner until it is too late to do it up right). She adds onions, stalk celery and a couple cloves of garlic. The only real difference is that we use low-salt canned stock (Campbells) rather than water and the usual cubes. Your 500 g is just over a pound; we generally use extra lean grade hamburger (we avoid the fat beef, being virtuous here so that we can grate some old cheddar or parmesan into it just before we eat). No pressure cooker, so takes about an hour.
I am the recipe fiend in the family, and I start getting stuff out and cutting about 2 pm (retired=redundant) for stew at six.