Soak the cashews for the filling for at least 2 hours (or in just-boiled water for 10 minutes), then drain.
To make the base, combine the rolled oats, ginger biscuits, pumpkin seeds and pitted dates in a food processor.
Process until the mixture becomes a sticky, crumbly texture. Add the melted coconut oil and process again to combine.
Press the mixture firmly into the base of a lined springform cake tin measuring either 18 or 20cm in diameter. Chill in the fridge while you prepare the filling.
In a small saucepan, vigorously whisk the agar agar powder, mango purée, maple syrup, lemon juice and vanilla extract. Heat for 3–5 minutes until the mixture simmers.
Drain the tofu and add to a jug blender with the coconut cream and soaked, drained cashews. Blend until completely smooth and creamy.
Add the warm agar agar mixture and blend again.
Pour the mixture over the chilled base and spread evenly. Return to the fridge to set for at least 2 hours (although overnight is best).
For the gel topping, combine the agar agar powder, mango purée, lime juice and maple syrup in a small saucepan and simmer for 2–3 minutes, stirring continuously.
Allow the gel to cool, then gently pour it over the set cheesecake. Chill in the fridge for at least 1 hour until the topping firms up.