Breakfast (winter): porridge (one can make it in the micro, a bit over 3 min on full blast, right in the bowl)
Breakfast (summer): muesli with yoghurt (around here one can get a somewhat thinner, 3% fat, yoghurt that is perfect for this application, I use a non-fruity muesli (the fruity ones can be 30+% sugar!).
Both of these are fairly quick and easy to make, in winter I need to run thr woodstove anyway in the morning, else the microwave make short work of porridge, and some milk-product + muesli are even quicker to fix.
For lunch I bring some leftovers and reheat in the micro (there is *always* one in every Swedish break room I've ever seen), or sensible sandwiches.
For bread I tend to bake myself, the last loaf was in the style of the Finnish "jälkiuunilimppu", an extremely slow rise full grain rye sourdough bread, but as long as it is full grain life is good.