Pistachio Paris-Brest

Directions

1. For the pastry cream
2. The cream needs time to cool completely, so make it first. Add the milk, pistachio butter (*read description for other options) and half of the sugar to a medium sized pan, put it on a medium high heat while you prep the yolks. Onto a bowl, add the yolks, the other half of the sugar, salt and give it a nice whisk, then add the corn starch and whisk again until smooth.
3. Once the milk starts to simmer (if using the pistachio butter, it might look like the milk curdled, but it'll be fine, don't worry), lower the heat and add a ladle full of it into the yolk mixture, while whisking, continue doing this until you used half of the liquid, then pour it back into the pan, set the heat up to medium and whisk constantly, once it thickens, cook it for 1 minute more and take it off the heat, Add the vanilla and mix well, then pour the cream into a bowl, cover with cling film, making sure it's touching the surface, and refrigerate it for about 1 hour, until completely cool.

1. For the choux pastry, recipe adapted from Edd Kimber
2. Preheat your oven to 180°C/350°F and line a baking sheet with parchment paper, set aside. Add the water, milk, butter, salt and sugar into a medium sized pan and bring it to a boil, measure your flour and keep it on the side. Once it boils, remove it from the heat, add the flour all at once and, using a wooden spoon or a heat-proof spatula, mix it very well until totally combined. Put the pan back on a medium heat and cook this mixture for 1 to 2 minutes, stirring constantly, or until a thin film forms on the bottom of the pan.
3. Put the dough inside a bowl of a standing mixer and, on a low speed, using the paddle attachment, mix it just to let the steam go out a little bit (doesn't need to be completely cool, but it does need to be at least warm, otherwise the heat will scramble the eggs), for about 1 minute or so. Then, on a medium high speed, add the eggs one at a time, mixing very well after each addition. When you get to last egg, whisk it seperately and add half first, if the dough is still too stiff, add the other half. The right consistency is when you dip the paddle into the dough and, when you lift it up, it forms sort of a V shape on the tip, it's not so loose that it will fall off the paddle and not so stiff that wouldn't stick to the paddle enough. You can also make this step entirely by hand, using a wooden spoon.
4. Place the dough into a pastry bag with a star tip and pipe little blobs of dough underneath the parchment, so it sticks, then, using even pressure and holding the bag vertically, pipe 6 rounds of pastry of roughly 5 cm in diameter, and pipe another round on top of the one you just made, so you have 2 layers of dough in each one (this will make them higher). Sprinkle some of the chopped pistachios on top.
5. Bake for 15 minutes, or until puffed up, then bring the heat up to 205°C/390°F and keep baking it for about 25 minutes longer, or until you can easily pull it off the paper and the top is golden brown. Then turn off the heat, close the oven door and leave it there for 10 minutes to dry out. Let it cool completely.
6. ASSEMBLY - Whisk the pastry cream a little bit to loosen it up and add it to a pastry bag fitted with a star tip. Cut the rings of pastries in half and pipe the filling into the base of each one, close with the other half and add a few more chopped pistachios around the sides. You can dust some icing sugar on top if you like. You can make each component of this recipe ahead, but only assemble it when you're about to serve.