- Preheat your oven to 350°F (175°C). 
- In a medium bowl, combine the graham cracker crumbs, granulated sugar, and melted butter. Mix until the crumbs are evenly coated. 
- Press the crumb mixture firmly into the bottom of a mini muffin tin to form a crust. Bake for 8-10 minutes until lightly golden. Remove from the oven and let cool. 
- In a separate bowl, whisk together the sweetened condensed milk, key lime juice, egg yolks, and lime zest until smooth. 
- Pour the key lime filling into the cooled crusts, filling each mini pie about 3/4 full. 
- Bake for an additional 10-12 minutes until the filling is set but still slightly jiggly in the center. 
- Remove from the oven and let cool to room temperature, then refrigerate for at least 2 hours to chill. 
- Before serving, top each mini dessert with a dollop of whipped cream and a slice of lime for garnish.