Melt the butter and stir with the ground oreos until the mixture resembles wet sand. Press the crust into the bottom and up the sides of the pan. Use a ⅓ cup measuring cup to help you pack in the bits into an even layer.

Bake the crust for 10 minutes. When it comes out of the oven, if it has bubbles in any areas use the same measuring cup to press it back into place. Leave aside to cool fully.

Set the cream cheese in a large bowl, and use the back of a rubber spatula or wooden spoon to press it into the bowl and remove any lumps. Add the sugar, salt and vanilla and use a hand mixer to beat until smooth. Add the sour cream and beat to combine. Set aside.

Chop the chocolate very finely and set it in a heatproof bowl. Warm it in the microwave for about 1 minute, then stir, then return it to the microwave for another 30 seconds. Stir and if the chocolate is mostly melted, then allow the heat from the melted chocolate and the bowl to melt the rest and stir until it’s smooth (if not, give it another 15-20 seconds in the microwave then stir until smooth). Leave aside to cool briefly.

Pour the chocolate over the cream cheese mixture and beat to just combine. Add the heavy cream and beat on low (or stir) until the batter is well mixed. Pour the filling into the crust and smooth it into an even layer.

Set the cheesecake in the fridge to chill for 4-12 hours, until firm.