Use an oven or toaster oven set to 350°F (175°C) for 20 to 30 minutes to reheat frozen Chicken Divan. To keep it from drying, cover with foil. Use a moist paper towel and the microwave for individual pieces .Hello all! I’ve got some Chicken Divanin in the freezer and I want to make sure it tastes as good as possible when reheated. Any suggestions on the best method to warm this up without drying it out? Appreciate your insights!