Season the chicken breasts with salt and pepper, then add Italian herbs and seasoning. This gives the chicken a delightful flavour from the start.
Heat the unsalted butter and olive oil in a pan. You can do this step directly if your slow cooker has a browning function. Pan-fry the chicken, skin side down, until it turns golden.
Once the chicken breasts are browned, turn them over and pour in white wine mixed with water or chicken broth. This adds depth to the flavour. Season with sweet paprika and garlic granules, and add the sun-dried tomatoes and chicken bouillon for an extra punch.
Cover and cook on the LOW setting for about 90 minutes to 2hours, or until the chicken reaches an internal temperature of 165°F.
If you want a thicker sauce, you can make an optional cornstarch slurry by mixing cornstarch with a bit of cold water and stirring it into the sauce about ten minutes before the cooking time is over. The cornstarch must be heated through to activate and thicken the sauce. If you are using sour cream, you can skip this step.
Move the chicken to one side and stir in sour or heavy cream until it's well incorporated. Add grated Parmesan cheese and fresh parsley for a creamy and rich finish. The combination of sour cream, heavy cream, grated Parmesan cheese, and flat-leaf parsley makes the dish incredibly flavorful.