Combine 1/4 cup butter and garlic powder in a small bowl, stirring well; set aside.
Combine breadcrumbs and next 5 ingredients in a shallow dish, stirring well.
Place each chicken breast between 2 sheets of heavy-duty plastic wrap; flatten to 1/2" thickness using a meat mallet or rolling pin.
Brush both sides of chicken with garlic butter; dredge in breadcrumbs.
Heat 1 tablespoon butter and 1 tablespoon olive oil in a large skillet over medium heat until butter melts. Add 3 chicken breasts; cook 4 to 6 minutes on each side or until lightly browned and done. Transfer to a serving platter; repeat procedure with remaining chicken, butter, and olive oil.
Meanwhile, combine whipping cream and remaining 4 ingredients in a small saucepan; whisk until blended. Bring to a simmer; cook 10 minutes or until mixture thickens slightly and coats the back of a spoon. Serve sauce with chicken.