In a mixing bowl, combine graham cracker crumbs, melted butter, and white sugar until it resembles wet sand. Press firmly into the bottom of mini dessert glasses.

In another bowl, beat together cream cheese and yogurt until smooth. In a separate bowl, whisk sweetened condensed milk and key lime juice, then fold into cream cheese mixture.

Divide filling; tint one half with green food coloring. Pipe the filling into dessert glasses, layering the two colors for presentation.

Cover and refrigerate for at least 2 hours until firm.

Garnish with whipped cream, lime zest, or fruit before serving.