Directions:

1. In a mixing bowl, combine the graham cracker crumbs and granulated sugar. Stir until well combined.
2. Pour the melted butter into the graham cracker mixture and mix until the crumbs are evenly coated and the mixture resembles wet sand.
3. Divide the graham cracker mixture evenly among serving cups, pressing it down firmly to form a crust layer at the bottom of each cup.
4. In a separate large bowl, beat the softened cream cheese with an electric mixer until smooth and creamy.
5. Gradually add the sweetened condensed milk to the cream cheese, mixing well after each addition until fully combined.
6. Add the key lime juice and vanilla extract to the cream cheese mixture. Mix until the filling is smooth and well incorporated.
7. In another bowl, whip the heavy cream and powdered sugar together using an electric mixer until stiff peaks form.
8. Gently fold the whipped cream into the key lime filling until no streaks remain, being careful not to deflate the whipped cream.
9. Spoon the key lime filling over the crust layer in each cup, filling them nearly to the top.
10. Refrigerate the cups for at least 4 hours or until the filling is set.
11. Before serving, top each cup with a dollop of whipped cream and sprinkle with lime zest for garnish.