I basically meal-prep a week at a time for meat and sometimes roasted veg. When I do have breakfast, it’s more often than not oatmeal (heat kettle, pour over, stir in cinnamon and maybe some brown sugar, then microwave a tad to speed things along) or a fried egg over rice. Rice cookers with a function to keep warm are also fantastic for only needing to cook rice a couple/few times a week (and bread and pasta are also rather quick, though I’ve had to give up gluten, sadly).