How can I reheat chicken without it getting rubbery or dry?
Try wrapping it in foil and cooking on a very low temperature in the oven or toaster oven. (Our oven has a "warm" setting that's ~170 F.) You can also include some water or broth in your foil packet but it won't penetrate much beyond the surface if the meat has been cooked before. It'll make that 1st bite taste more moist but in the long run it won't do much.