Step 1

Add softened cream cheese, sweetened condensed milk, lime juice and 2/3 of the lime zest to a  large mixing bowl, and beat on high until smooth and creamy (about 4 minutes).

Step 2

Transfer to a graham cracker crust.

Step 3

Sprinkle reserved lime zest in top, and refrigerate until filling is set, about 3 to 4 hours.

Step 4

Serve chilled, and garnish with extra lime slices, if desired.