In a shallow dish, mix flour with garlic powder, salt, and black pepper.
Butterfly the chicken breasts to create 4 even pieces.
Dredge each piece in the flour mixture and shake off excess.
Heat olive oil and 1 tbsp butter in a large pan over medium-high heat.
Cook chicken for 3–5 minutes per side until golden and fully cooked. Remove and set aside.
Lower heat to medium and sauté garlic for 1–2 minutes until lightly golden.
Pour in chicken stock and scrape the pan to release flavor.
Add remaining butter and whisk until melted and combined.
Stir in parsley and season to taste.
Simmer until slightly thickened, then return chicken to the pan.
Spoon sauce over the chicken and serve with optional lemon juice.
This Garlic Butter Chicken comes together quickly and creates a rich, velvety sauce.