Poached eggs on a bed of wilted spinach, I used to react to mushrooms but can manage them now so I’d have them too. Or boiled dippy eggs with carrot “soldiers” if you can’t eat toast. Can you eat gluten/free bread? Greek yogurt with a selection of berries, and chia or flax seeds. Fried egg with bacon, scrambled egg with smoked salmon? I have IBS too but after following the FODMAP elimination method I’ve been able to re-introduce a lot of former trigger foods as long as I don’t have them at the same time, and can enjoy porridge again.