Break up the biscuits.
Preheat an oven to 180 ºC.
Grease a springform tin and line with parchment paper.
Fit the K Beater to the machine.
Add Ingredients 1 (biscuits, sugar, butter, lime zest) into the Mixer bowl.
Attach the Mixer bowl to the machine and fit the splash guard.
Start the machine on speed min and mix for about 4 minutes or until you reach a sand-like mixture.
Press the mixture into the base of the tin in an even layer.
Place into the preheated oven and bake for 10 minutes at 180°C.
Let cool and reduce the oven to 160°C.
Retrieve, clean the Mixer bowl and fit the Whisk Tool.
Add the first of Ingredients 2 (yolks) to the bowl.
Start the machine on speed 2 and mix for 1 minute.
Add the rest of Ingredients 2 (condensed milk, zest, juice) to the bowl.
Mix on speed 1 and mix for 1 minute.
Pour the lime mixture on to the biscuit base
Add the first two of Ingredients 3 (whites, tartar) into the Mixer bowl.
Attach the Mixer Bowl to the machine.
Start the machine on speed 4 and mix for 3 minutes, keep the machine running.
Add the rest of Ingredients 3 (caster sugar) while the machine is running.
Mix on speed 4 and mix for 3 minutes or until stiff peaks form.
Spoon the meringue on to the lime mixture and spread to form a peak in the middle.
Bake for 20 minutes at 160°C until the meringue is golden and toasted in places.
Cool and chill in the fridge for at least 4 hours before serving.