For the cream:

1. I always start by boiling the shelled pistachios for 3 minutes to soften them. Then drain them and set them on a clean tea towel to dry.
2. Then use the tea towel to rub the pistachios to loosen the skins. You want to separate the pistachios from the skins and discard them. This step does take a little time but I promise it’s worth it.
3. Tip the pistachios into a food processor with 100ml of the milk and 1 tablespoon of icing sugar. Blitz for around 5 minutes until the pistachios turn into a smooth paste, scraping down the sides every minute or so. Be patient – to begin with, it will resemble breadcrumbs but eventually, it will turn into a paste – this is important.
4. Heat the rest of the milk along with the butter and white chocolate in a saucepan and heat gently until melted.
5. Scoop the pistachio paste into a blender and then pour in the melted white chocolate mixture. Blitz until extra smooth and creamy.

For the syrup:

1. Add the sugar, water and vanilla to a pan. Heat over medium and bring to a boil, stirring until the sugar is dissolved. Simmer for one minute then remove from the heat.

To assemble:

1. Heat the oven to 180c.
2. Slice the croissants in half and brush each side with sugar syrup. Place on a baking tray. Spread the bottom with Nutella then pipe on some pistachio cream. Sandwich together and pipe the top with more pistachio cream. Scatter with chopped pistachios and place in the oven for 15-20 minutes until toasty and golden.
3. Dust with icing sugar and drizzle with melted chocolate or more Nutella and enjoy!