keeping a good variety besides having their base feed is important and your chickens will tell you what they like and don't like so you can adjust. When we started we would give one new item at a time that wasn't listed on do not feed to chickens list, to see how they reacted. mine will beat the dogs up for their scaps if it's got vegetables especially if they have the skins on still lol, garlic, chili powder, any type of fruit. But mine free range most the time unless we are well below zero for temps. winter is the only time they do not have lacto fermented feed available also , we have enough trouble keeping the water unfroze as we are in the north.
Here's what mine will eat in order of their favorites, your chickens may have a different preference though. This is just some ideas but ours usually have a couple of different choices and they eat what they want. This has also helped train them to stay out of the garden after taking their treats away for a couple of days for getting into it they now wait for us to call them to the garden:
buttercup squash
sugar snap peas
watermelon
strawberries
lettuce
raw spinach
carrots
apples they tend to just like the peels unless I actually dehydrate them in slices
potato and skins
grains they prefer:
corn
oats
any type of seed
Table foods they prefer:
any kind of yogurt
anything that we are eating and have left overs so I make sure not to add much salt and everyone can add it to their plate
well cooked meat, hamburger sausage etc
scrambled egg
oatmeal
boiled rice
rye and pumpernickle bread in small amounts
corn tortillas