Mix all of the ingredients (except the chicken breasts and fresh parsley) together in a large bowl or a Ziploc bag. Add the chicken and rub the marinade all over to ensure proper coverage. Get some of the marinade under skin as well. Marinate in a fridge overnight or up to 24 hours. I typically start the night before and get about 20-24 hours of marination. If pressed for time, go for at least 30 minutes to 2 hours. The chicken won't have the same tenderness but will still taste amazing.
Pan-sear the chicken skin side down for about 3-4 minutes or until the skin is dark golden brown.
Transfer the chicken into a 6-quart slow cooker, positioning the chicken breasts skin side up. Pour the marinade all over the chicken.
Cook on Low for 2 hours. Switch the slow cooker to Warm to keep the chicken warm until ready to serve.