1. Add the flour and salt to a large bowl. Cut the butter into small cubes and toss it in the flour to coat it evenly. Use a pastry blender* or knife and cut the butter into pea-sized pieces. Combine the cold water and vinegar (you can cool it further down with some ice cubes). Add about half of the water-vinegar mixture to the bowl and mix in. Gradually add more while working the dough until it starts sticking together – you might not need all the liquid. The dough should not feel wet. Some dry spots in the dough are fine. Wrap the dough in plastic wrap and place it in the fridge for about one hour.

2. Roll out the dough into a rectangle on a lightly floured surface. Fold the long sides towards the center in thirds, one layer over the other, to create a three layer package. Repeat this process two more times – roll out to a rectangle and fold it towards the center. After the last round of folding, wrap the dough once more in plastic wrap and let it rest in the fridge for at least two hours or (even better) overnight. The dough can be stored in the fridge for up to 3 days.

3. Roll out the dough on a floured surface slightly larger than a 9-inch pie dish*. Place the dough inside the pie dish, press it down, tuck in overlapping dough around the edges and crimp to your liking. Prick the bottom several times with a fork. Place the pie dish in the fridge for about 20-30 minutes.

4. Preheat the oven to 220°C (425°F). Place a piece of baking parchment on the dough and fill up with baking beans*. Blind bake the pie crust for about 15-16 minutes, take out, remove the baking beans and baking parchment and bake another 6-8 minutes until the bottom slightly golden brown – it should not look wet anymore. Take out of the oven and let cool down completely.

5. For the filling, chop the chocolate coarsely and add it together with the cocoa powder, and butter to a microwave-safe bowl. Heat this mixture slowly in the microwave (in 30sec intervals) until the chocolate and butter have melted completely, and you got a nice and smooth chocolate sauce. Let cool down for a moment.

6. Preheat the oven to 180°C (350°F). Add both sugars and the eggs to a large bowl and mix on high until pale and doubled in volume – takes about 2-3 minutes. Add the cooled chocolate sauce, as well as the salt and vanilla extract, and stir until very well combined. Next, add the flour to the bowl and fold it in with a rubber spatula – do not over mix the batter. Pour into the cooled pie crust, smooth out the top and bake for 30-40 minutes or until a toothpick inserted into the center of the pie comes out (almost) clean. It’s better to under bake the pie slightly than over bake it (if you want a fudgy texture). Take out of the oven and let cool down completely on a wire rack. After that, leave it in the fridge for an hour before serving, so it can set completely. Store leftovers at room temperature up to 2 days – if your kitchen is warm, better store the pie in the fridge and let it come to room temperature again before serving.