In a bowl, combine olive oil, lemon juice, minced garlic, salt, and black pepper.
Mix well to create a marinade.
Add the chicken breasts to the marinade and let them sit for at least an hour in the fridge.
Letting them sit longer intensifies the flavors.
Heat butter in a skillet over medium heat.
Add the chicken breasts and cook until browned on both sides, about 5-7 minutes per side.
Remove chicken from the skillet and set aside.
In the same skillet, add the remaining marinade, chicken stock, and thyme.
Bring to a simmer.
Return the chicken to the skillet, cover, and let it cook for another 10-15 minutes until thoroughly cooked.
Sprinkle Parmesan cheese before serving.