Grease the 20cm pie dish with a little butter.

Place the light digestive biscuits, butter and 2 tsp of the sugar into a food processor and pulse until it has an even large crumb texture.

Add 1-2 tbsp water to the biscuit and mix in to combine.

Press into the pie dish making sure the crust is even all around and up the sides. Refrigerate the crust for 30 minutes before you bake it. This will help keep the crust together when slicing later.

While the crust is in the fridge, preheat the oven to 180C. Bake the crust in the oven for 8-10 minutes until the crust is golden. Remove from the oven and allow to cool before filling.

Squeeze the juice from the limes into a bowl and add the gelatine. Allow to soften for a couple of minutes before warming in the microwave for 30 seconds to dissolve the gelatine.

In a large bowl combine the cream cheese, yogurt, the rest of the sugar and the zest of a lime. Add in the lime juice then mix well by hand or with an electric whisk, until everything is evenly combined.

Pour the filling mix into the digestive biscuit crust.

Chill the pie for at least 3 hours before serving.