Steps
- Crush 25 chocolate sandwich cookies with their filling and mix with 75g of melted butter. Press into the base and sides of an 8¾in / 22cm pie dish. Refrigerate.
- Warm 625ml of whole milk with 75g of superfine sugar over medium-low heat until steaming. Whisk 6 egg yolks with 2 tablespoons of cornstarch in a bowl.
- Whisk a little hot milk into the yolks, then whisk everything back into the pan. Stir over medium-low heat for 3-5 minutes, until thickened.
- Off heat, whisk in 100g of chopped salted butter, 200g of chopped dark chocolate with at least 70% cocoa solids, and half of 2 teaspoons of vanilla extract until smooth.
- Fill the crust and press parchment against the surface. Chill for 3-4 hours, until set.
- Whip 300ml of heavy cream, 2 tablespoons of icing sugar, and the remaining vanilla to soft peaks. Spread over the pie and finish with chocolate shavings.