Honestly anything with a bit of fat and protein will help your body absorb the vitamins better, so I'd suggest having some toast with peanut butter, an egg, or even just a bowl of oatmeal with milk before you take them. My gynae mentioned that taking prenatals on an empty stomach can make you feel queasy, so I always had something light like yogurt or a banana first and it made a difference. The key is just not to take them completely empty-stomach lah.
Honestly, I just eat what I usually do, which would be bread. Fried eggs on toast is a good option and doesn't need too much time to prep