Some types of chicken will remain tough when cooked in a slow cooker or crockpot if it does not have a lot of connective tissue.
Chicken breasts are one of the types of chicken that will still remain tough even when slow cooked a chicken breast also has less fast and can become dry and chewy or rubbery when cooked for too long.
Chicken that has a lot of connective tissue will get more tender the longer you slow cook it as the connective tissue will turn to gelatin after slow cooking in moist heat for several hours.
Other types of chicken such as chicken breast will usually not become more tender the longer they are slow cooked.
Some types of chicken such as chicken thighs and chicken drumsticks become and get more tender the longer you cook them but chicken breasts become less tender the longer you cook them.
Dark meat has a lot of connective tissue which dissolves into gelatin as the meat cooks which renders it tender and juicy.
You should allow at least 15 minutes to let the chicken come to room temperature before cooking it which will make the chicken cook more evenly.
If the chicken is frozen it should be thawed out before cooking so it will cook evenly and properly.
Take the chicken out of the refrigerator 15 minutes before cooking.
If you don't let chicken rest after cooking it leads to a loss of more flavorful juices when the chicken meat is cut.
The internal temperature of the chicken meat will always continue to rise a little during the resting period so you should remember to also remove the chicken meat from the oven or grill prior to it reaching it's target temperature for doneness.
To make the best tasting check when the chicken is finished cooking, just like a good steak, chicken needs to rest.
Once you've hit 165 degrees on the chicken, stop the heat and let the chicken rest for few minutes before cutting the chicken, so the juices redistribute themselves back through the meat.
To store cooked chicken, make sure that it does not sit out at room temperature for more than two hours or more than one hour in temperatures above 90°F.
Ensure the chicken is cooled to room temperature within two hours before stowing it in the refrigerator or freezer.
Also after chicken is cooked, the chicken must be kept hot (140°F or warmer) to prevent bacteria from growing on the chicken before you eat or store it in the fridge.
Cooked chicken should be refrigerated within no more than 2 hours after cooking or removal from an appliance keeping it warm.
Safely cooked chicken can vary in color from white to pink to tan.
All chicken meat should reach a safe minimum internal temperature of 165 °F (73.9°C) as measured with a food thermometer.
For whole chicken, check the internal temperature in the innermost part of the thigh and wing and the thickest part of the chicken breast.