In medium mixing bowl, stir together softened butter, minced garlic, garlic powder, and salt until ingredients are fully incorporated. Set aside.
Heat large skillet over medium-high heat. When skillet is hot, add avocado oil and swirl skillet to coat evenly.
When oil is hot and shimmering, add chicken breasts. Sauté chicken 4 to 5 minutes or until golden, then flip and sauté another 4 to 5 minutes or until chicken is completely cooked-through and no longer pink internally. Transfer chicken to plate and set aside. Note: if chicken is not cooked-through and firm by this point, reduce heat to low and cover skillet with lid. Cook chicken another 2 to 3 minutes or until cooked-through and firm.
Reduce heat under skillet to low. Carefully pour in wine to deglaze skillet and use spatula to scrape up any browned bits of chicken that may have stuck to skillet. Bring liquid to low boil, then cook until liquid has reduced by 50%. There should be roughly ¼ cup liquid left in skillet.
Add garlic butter mixture and chopped parsley (if using) to skillet. Stir well until garlic butter has melted completely, then return cooked chicken to skillet. Spoon garlic butter sauce over chicken breasts, then plate chicken with desired sides and serve immediately.