I think the key here is pre-planning, so you do have time to eat a quality, sustaining breakfast. For oatmeal, you can either buy the small individual pkts or DIY and buy the large cylinder oatmeal and pre-measure them into ziplock baggies. I bought a cordless electric tea kettle & it's been one of my most used pieces of kitchen equipment (costs ~$20). You press down a button while you're getting ready for work. It automatically shuts off when it has reached its boiling point... so, then you have hot water for oatmeal, tea, coffee via french press. The night before, I would cut up fruit, so that it's ready to eat. Also, bagel & cream cheese or peanut butter toast are all good complementary things that stick with you.