I used to work at Arby's and made a ton of chicken salad. I don't know how the measurement are if you want to make a small batch, but I can give you the ingredients and you can just tweak them to your taste. All you need is grilled chicken, cut into chunks, mayonnaise, seedless purple grapes and red apples. Large dice the apples and cut the grapes in half. We usually added pecans to the mix, but you can always leave them out.

Mix grilled chicken, apples, grapes, pecans and mayonnaise. The secret here is to not drown it in mayonnaise, but just so the mayo can fully cover the other things. Find some honey wheat bread and toast the side that will be facing outside. Put some lettuce on the bread and spoon the chicken salad on the leaf lettuce. Cover with other piece of bread. That's really all you need.