My girls, more or less, will eat anything that's in my hand. In fact, they are so trained that I can be sharing something (lettuce, apple, pear, ...) and some will fall to the ground and the won't look twice at it until I pick it back up. When they were younger, I would go out and pick clovers and things right in front of them, then hold it out for them and they would gobble it up, and chase each other and fight over it if necessary. Even though there were TONS of clovers all around them. Funny girls.
Things they like: apples, bananas, pears, grapes, lettuce (especially the Welsummers!), cabbage, spinach, baked goods like bread (but I try not to give them too much of that, I don't want them to get overweight), strawberries, other berries like blackberries and raspberries, songbird/wild bird seed (they do a great job cleaning up below the wild bird feeder), yogurt, and I have a silkie that really likes yogurt covered dog food pieces, Yuck! As far as bugs go, they LOVE Jerusalem crickets and J. cricket larvae! Also, spiders, worms, and flying bugs like moths and flies when they can catch 'em (that's definitely funny to watch!).
Oh, I have noticed they are not too thrilled with strawberry tops (the green leafy part), go figure. And most of the tomato they will snub, but they gobble up the seeds and a bit of the lycopene part (clear jelly-like stuff around the seeds). That's alright, everything else goes in the composter.
Bottom line, they like variety, like anyone else. If I feed them bananas for too many days in a row, they get that look on their face, like "Again?
" Spoiled, spoiled girls.