Mitzi - how do you know the proportion of water to veg for different veg?
How do you know which ones will go together and which ones won't?
I just eyeball it. Same with the flavours - it's just something I have a rough idea will go together (like frozen butternut squash, chickpea and spinach/sad looking salad leaves from the fridge go really well with curry paste, a blob of Tamarind paste and a splash of lemon juice makes reduced in the pan passata cartons taste and feel like Heinz Tomato soup (add red chilli flakes if you want something even nicer - and a gloop of tomato puree if it's not quite there yet) -
or if you heat up half a pan of stock with an eggcup of mirin/sake and an eggcup of soy, you can throw in udon noodles, random frozen veg (peas, broad beans, edamame beans, green beans, sweetcorn), a few frozen prawns or leftover cooked chicken with a spring onion and the sweet, crunchy and smooth textures all balance one another out. If you like, chuck a pinch of sesame seeds or a splash of sesame oil/chilli flakes on top, but the residual heat of the stock will warm the veg and prawns through whilst you're getting the bowls out.
I don't do dairy much, so can't get recipes online (and most of the few ones that are available are so much of a faff, I can't be arsed to follow them, anyway) - the only way to try is to come up with the ideas and see how they work out. If in doubt - add more veg - is my rule of thumb.
It definitely keeps the nutrients in the soup, though, as they're made with the cooking/heating liquid, most are only done until just cooked/hot (some are straight from the freezer), nothing is peeled, so the vitamins just under the skin are retained, they have up to all their fibre and they aren't overburdened with sugar, salt, starch and additional fat.