masterstroke
/ˈmæstərˌstroʊk/
noun
- A very clever or skillful action that achieves a great result, especially in a difficult situation.
- Adding a pinch of cinnamon to the recipe was a masterstroke that made the dish famous.
- Hiring that young designer was a masterstroke that saved the company.
- The general's surprise attack at dawn was a masterstroke of military planning.