Plum and Lime Upside-Down Cake

The magic of this gooey upside-down cake featuring the best of the season’s juicy, sweet plums lies in the lime (yes, lime!) caramel. After many tests in my quest to deliver those sour citrus notes as soon as you take a bite, I landed on a concoction that’s sweet and buttery with a zesty tang. The main takeaway to prevent a caramel seizing up on you is to reduce the sugar and lime juice together from the start. The result is a luscious sauce with deep caramel notes and sharp lime flavor. Mission accomplished! The sponge is soft and also limey thanks to the fresh zest reinforcing the caramel. Just try to resist going in for another slice. —Rachel Gurjar