Preheat oven to 350 degrees. Line 12 cupcake cups with paper liners.
Mix together crumbs, sugar and butter and divide evenly among cupcake liners. Press down to form crusts.
Prepare Filling: Beat the cream cheese, condensed milk and sugar until smooth. Beat in lime zest, lime juice and vanilla. Stir in the egg. When egg is fully blended, stir in the flour.
Divide the batter evenly among the mini pie crusts and bake for 25 minutes or until the cakes appear set (if they crack, it’s okay). Let cool at room temperature, then chill for several hours or until very cold.
Top with whipped cream and a stemmed cherry or slice of lime.
Notes
For extra lime flavor, add about ¼ teaspoon of Key lime extract or a tiny bit of lime oil.