Do not overfill your crockpot—keep it no more than two-thirds full for best results and to avoid spills., Browning the chicken beforehand is optional, but adds extra flavor., Add dairy ingredients such as heavy cream and Parmesan cheese in the last 20-30 minutes of cooking to keep sauces smooth and prevent curdling., Use a meat thermometer to ensure chicken reaches 165°F for safety and optimal juiciness., To thicken the sauce, stir in a cornstarch slurry (equal parts cornstarch and cold water) near the end and cook for 10-20 minutes until thickened., Try to avoid opening the crockpot lid during cooking to maintain temperature and timing., Chicken thighs can be substituted for chicken breasts for juicier results., For dairy-free version, substitute heavy cream with full-fat coconut milk and Parmesan with nutritional yeast.