I had high hopes for this one...ready-made tomato soup with no added sugar and available in small, one person/portion-sized cartons (300 g). Here's a pic, so you know what to look out for.
tomato puree (30%)
oregano - N.B. a powerful anti-fungal!
Nothing that should antagonise (encourage?) any lingering yeasty-beasties. But, for me, the flavour was too sharp and slightly bitter (really needs sugar sadly), and I didn't get on well with the large chunks of tomato (I prefer a smooth texture). Still, others might disagree - it's worth giving it a go.