Line the inside of a 9" spring form pan with plastic wrap.
Mix pretzels and butter together. Press pretzel crumbs into spring form pan.
Freeze until filling is ready.
Mix cream cheese until fluffy.
Add lime juice and zest, sugar, yogurt. Mix together until smooth.
Add food coloring if desired.
Fold in whipped topping.
Pour onto crust and smooth.
Freeze for 3 hours or overnight.
Let sit for about 10 minutes before serving.
Top with additional whipped topping, Garnish with mint leaves and lime slices.