For the vegetable leftovers, first cook noodles, rice or anything else you like. In the meantime, wash, clean and coarsely chop all leftover vegetables in a pan. Cut onion, carrots and pointed peppers into thicker rings.
Coarsely slice the cucumber with peel (can be zucchini, of course), add about 10 cherry tomatoes (can be others, of course) and a can of peeled tomatoes.
In a cast iron pot (if available) steam the vegetables on low heat in their own juice and season with salt, pepper, possibly sugar and fresh herbs.
Add a little water and finish steaming. At the end, season with a dash of vinegar and a little salt and serve.