What has worked best for us (me and my kids) is a combination of b and d vitamins, liquid magnesium, and homemade breakfast bars that are a combination of dates, nuts, healthy fats, some dried berries, seeds, quinoa, oats, and cocoa. It takes a lot of planning to make, but the batch lasts a couple of weeks and it's a great combination of carbs, fat, and protein in the morning.
There are a lot of ingredients that go into those bars, but protein powders (the 5 or 6 kinds that I've tried) make me sick, so the bars are a replacement. I originally developed the recipe for a friend I had who would often forget to eat and get faint later in the day. He was vegan and I have Celiacs, so the quinoa is the key ingredient, as quinoa is a complete protein.
My 16-year-old forgets to eat, too, and recently fainted in the hallway. We're tracking their food intake and planning some eating times with more nutrient-dense foods, with some success so far.
We like to cook in our family, but we hate to come up with meals. For a while this year, we did the Blue Apron meal service for part of our cooking, which gave us ingredients and recipes. Me and Mx. 16 love sameness, my youngest needs variety, so it was a good enough compromise.
Now we source ingredients from the recipe cards and have cancelled the service. The ingredients list helps keep me organized when I plan a shopping trip, and the recipe itself is a fairly balanced meal.
What I wouldn't give for a nice, thick slice of sourdough bread, though...
I sort of feel like the original intent of the post was lost for a bit there. Vitamins b, d, and magnesium. Homemade breakfast bars. Keep forgetting to add more greens into my diet. Hope you find something that works.