Spray a 9 inch round pie dish with non-stick spray and set aside. Preheat the oven to 350°F (180°C).
Add the vegan digestives or graham crackers to the food processor and process into crumbles. Melt the vegan butter and mix in with the cookie crumbles and then place into the prepared pie dish and pat down firmly. Use the bottom of a measuring cup to press down firmly along the bottom and work the crust up along the sides.
Place the pie base into the oven and bake for 10 minutes. Remove from the oven and leave to cool.
Pour your vegan condensed milk out into a bowl and place into the fridge to cool and thicken.
Add the coconut cream (separated hardened cream at the top of 2 chilled cans) to the bowl of a stand mixer, leaving the watery parts behind. Starting at slow speed gradually increase speed until the cream is whipped. For best results in this recipe, you need the cream to be very firm and well whipped with stiff peaks. If yours is a bit on the softer side, add in a ¼ - ½ tsp of xantham gum and whip again. It will thicken fast.
Squeeze the lime juice and grate the lime zest.
Add the lime juice, lime extract and lime zest to the bowl with the condensed milk and whisk with a hand whisk to combine. Then fold in the whipped coconut cream.
Pour this over the cooled crust and place into the fridge for a few hours to set. If you want to speed it up a bit then you can put it into the freezer, just don't forget it in there or you'll have to wait for it to thaw!
Decorate with lime zest and serve.