Meanwhile, whisk 1 large egg, 1 large egg yolk, ½ cup (100 g) granulated sugar, ¼ cup fresh lime juice, and ½ tsp. Diamond Crystal or ¼ tsp. Morton kosher salt in a small saucepan. Place over medium heat and cook, whisking constantly, until sugar is dissolved, about 1 minute. Continue to cook, adding 6 Tbsp. unsalted butter, cut into pieces, a piece at a time and whisking to incorporate before adding more, until all of the butter has been added and curd is thick enough to coat a spoon, 2–3 minutes. If curd is not thick by the time all of the butter has been added, continue to cook, whisking constantly, about 2 minutes more. Strain through a fine-mesh sieve into a medium heatproof bowl. Let cool slightly, then cover, pressing plastic wrap directly onto surface. Chill until cool, about 1 hour.
