Above all, it is very important to start checking the internal temperature of chicken breasts after about 25 minutes in the oven. As soon as the chicken breasts reach an internal temperature of 165ºF at the thickest part, take them out of the oven because they are done. Make sure to test the biggest/thickest chicken breast for doneness. If the biggest one is done, so are all the smaller/thinner ones. Moreover, the addition of the cream of chicken soup will help keep the chicken moist during the cooking process. If your chicken breast gets over cooked, check the internal temperature earlier the next time you cook your chicken.