Preheat oven to 325°F. Line a 12-cup muffin tin with paper liners or lightly grease.
Mix crumbs, 3 tbsp sugar, and melted butter. Press 1 tbsp into each cup to form crusts.
Beat cream cheese and 2/3 cup sugar until smooth. Add eggs one at a time, then sour cream, lime juice, vanilla, and zest.
Spoon filling over crusts, filling almost to the top. Tap tin to release air bubbles.
Bake 16–20 minutes until centers are set but slightly wobbly. Cool on a rack 30 minutes, then chill at least 2 hours.
Top with whipped cream and extra zest before serving.