Add chicken to the crock pot. Top the chicken with the butter, dry white wine, minced garlic, oregano, salt and pepper.
Cover and cook on low for 5-7 hours or on high for 2.5-3.5 hours until the chicken has an internal temperature of 165 degrees F but is not shreddable.
After this time, remove the chicken. Then stir together the cornstarch and heavy whipping cream in a small bowl.
Whisk this mixture into the sauce in the crock pot, stir the spinach and the parmesan cheese into the sauce and place the chicken back on top.
Cover and cook on low for 30 minutes to thicken and heat the sauce through and the spinach is slightly wilted.
Serve warm as is or over pasta and enjoy!
