I don't remember exactly what I ate in early recovery. I just know that any time I feel bad, I try to eat 'easy' food, like soup and toast and bananas. Veggies and fruits too. I did indulge my craving for dark chocolate tho, and still do, but my diet is mostly healthy stuff.
Not having an appetite could just be due to being in early recovery. It's a time of things being out of balance, when your body and brain have to readjust to normal functioning again.
If you're concerned about getting the proper nutrition, you could even drink those nutrient-dense drinks, just to make sure you're getting the vitamins and minerals you need.
Another way to get up an appetite is to exercise. Even just moderate walking once or twice a day can help.