Heat the oil in a large, nonstick skillet over medium-high heat. Add the chicken and cook until golden, about 4 minutes, then flip and cook on the other side until cooked through, about 4 more minutes. Remove the chicken to a plate and wrap with foil to keep warm.
Add the garlic to the pan and cook 30 seconds. Add the remaining ingredients to the pan. Stir and bring to a boil; continue stirring and boil until the mixture is slightly thickened.
Return the chicken to the skillet; spoon the sauce over the chicken to coat.
Serve chicken over rice, if desired, with sauce drizzled on top.