A true clean-out-the fridge soup that makes the case for always keeping at least one tub of miso in the fridge. (Have you tried chickpea miso, yet? Please do if you see it. The difference between corny tasting garbanzos and slightly grassy soybeans is subtle but noticeable.)
The idea is to get a pot of water on the stove to boil, then put a cutting board nearby. Working with the food that takes the longest to cook, start chopping and dropping. For lunch the other day, there were some lovely striped summer squash lollygagging in the produce bin with a couple of sort-of-shriveled cayenne peppers and a red onion. More rummaging turned up an almost empty jar of fresh ginger. You get the idea. Instead of the tofu at the end, you could crack in an egg, add a spoonful of cooked beans or grains, or stir in a little simply cooked meat.