2 1/4 cups whipping cream
3/4 cup plus 1 teaspoon sugar
3 tablespoons fresh lemon juice
2 tablespoons fresh lime juice
1 teaspoon grated lemon peel
1 teaspoon grated lime peel
Bring cream and 3/4 cup sugar to boil over medium-high heat, stirring until sugar dissolves. Boil 3 minutes, stirring constantly, adjusting heat as needed to prevent mixture from boiling over. Remove from heat. Stir in lemon juice and lime juice and cool 10 minutes. Stir mixture again and divide among six 1/2-cup ramekins or custard cups. Cover and chill possets until set, at least 4 hours or overnight.
Mix remaining 1 teaspoon sugar, lemon peel, and lime peel in small bowl. Sprinkle atop possets