1 medium grapefruit, peeled, sliced ¼ inch thick, and seeded
Instructions
Preheat oven to 350°.
In the work bowl of a food processor, process cookies until finely ground. Add melted butter and ¼ teaspoon salt; pulse until mixture is well combined and holds together when pinched between fingers, stopping to scrape sides of bowl. Using the bottom of a measuring cup, firmly press mixture into bottom and up sides of a 10-inch cast-iron skillet.
Bake until crust is fragrant and set, about 10 minutes. Let cool completely on a wire rack.
In a small cast-iron Dutch oven, whisk together 1¾ cups plus 2 tablespoons sugar, cornstarch, ginger, and remaining ¾ teaspoon salt; whisk in grapefruit juice and lime juice until well combined. Cook mixture over medium heat, stirring occasionally, until steaming.
In a medium bowl, whisk egg yolks. Gradually whisk half of hot sugar mixture into yolks until combined. Whisk yolk mixture into remaining sugar mixture in pot, and bring to a boil over medium-high heat, whisking constantly. Cook, whisking constantly, until mixture registers 203° on an instant-read thermometer.
Strain mixture through a fine-mesh sieve into a large bowl, discarding solids. Whisk in butter, 1 tablespoon at a time, until melted. Whisk in grapefruit zest. Spread curd into prepared crust. Refrigerate pie, uncovered, until filling is cold and set, at least 4 hours or overnight.
Place grapefruit slices on a rimmed baking sheet, and pat dry with paper towels. Sprinkle remaining 1 tablespoon sugar onto fruit. Using a handheld kitchen torch, toast grapefruit until lightly browned and sugar is caramelized. Top pie with fruit; serve immediately.
Recipe by Southern Cast Iron at https://www.southerncastiron.com/grapefruit-lime-pie/