In a large bowl, combine the ranch dressing, olive oil, garlic powder, onion powder, paprika, salt, and pepper.
Add the chicken cutlets and toss to coat evenly.
Cover and marinate in the refrigerator for at least 30 minutes, or up to 2 hours for more flavor.
While the chicken is marinating, prepare the creamy garlic sauce by mixing together the sour cream, mayonnaise, minced garlic, lemon juice, parsley (if using), salt, and pepper in a small bowl.
Preheat a large skillet over medium heat.
Remove the chicken from the marinade and let any excess drip off.
Cook the chicken cutlets in the skillet for about 5-7 minutes per side, or until they are golden brown and cooked through (internal temperature should reach 165°F).
Once cooked, remove the chicken from the skillet and let it rest for a few minutes.
Serve the chicken cutlets drizzled with the creamy garlic sauce.