We did/ still do -
Porridge - with some combination of banana, berries, grated apple, grated carrot and courgette, milled seeds, ground almonds, nut butter, dessicated coconut, cinammon or nutmeg, sultanas, stewed fruit - obviously only a couple of those at a time 
Porridge muffins - take leftovers of whatever version of porridge I’ve made, add extra oats to thicken mixture, spoon into silicone muffin case and bake for about 30 mins - these freeze great so I do a few whenever I make a big batch of porridge and then keep them in the freezer, 30 seconds in the microwave and they’re ready to serve again
Pancakes - either the baby banana 3 ingredient ones or American style but with no sugar - we use egg in both but there’s loads of recipes out there for egg free versions, look up SR nutrition she has some options or the what mummy makes books do
Toast with avocado, nut butter, cream cheese and raspberries, mashed banana, pumpkin seed butter is also good. Now my dd is older I sometimes do marmite but it’s salty so not very often. Also I’ve made ‘jam’ by boiling soft fruits with chia seeds before which again there’s different recipes online and doesn’t take much time. Sometimes hummus on toast too though that tends to be a lunch option
Greek yoghurt with whatever - fruit, oats, crumbled up cereal, any of the porridge toppings mentioned above, or chia jam
Other cereals - weetabix, shredded wheat bitesize which has no added salt/ sugar, sometimes the whole grain Cheerios but they’re hard to find round here for some reason
Crumpets with different toppings
Chia pudding - it’s a what mummy makes recipe again, from memory it’s just under a punnet of raspberries mashed with a fork, squeeze of lemon juice, add 3 tablespoons chia seeds and about 100ml of milk (cow or almond/ whatever you use) then mix it up and leave in fridge overnight. Serve with porridge. I like it with honey or maple syrup but my daughter went nuts for it just plain, haven’t done it in ages actually so might try again at the weekend