Line a 12-cup muffin tin with liners and set aside.
In a bowl, stir together the graham cracker crumbs and brown sugar. Add melted butter and stir until well combined.
Divide the crust mix between the liners and firmly press down to create even mini crusts.
Put whip cream, yogurt and lime juice in a large bowl and gently fold together until just combined.
Divide the filling evenly and level out. Add some lime zest to the tops of each before freezing.
Put the muffin tin into the freezer for 2 hours or longer until frozen solid.
Once frozen, pop out and garnish with whip cream. Enjoy!