Since Starbucks announced its 2025 summer menu on May 19, the Iced Horchata Oatmilk Shaken Espresso has been a breakout hit.

Starbucks has a horchata hit on its hands. A newcomer on the specialty coffee chain's summer menu, the Iced Horchata Oatmilk Shaken Espresso, is selling at a better pace than any Iced Shaken ...