Valentine’s Day raspberry and pistachio tart

Directions

• 1. Step 1For the pastry, in a food processor pulse the flour, icing sugar and a pinch of fine salt until combined. Add the butter and pulse until the mixture resembles fine breadcrumbs. Alternatively rub the butter into the flour mixture using your fingers. 
  2. Step 2Add the egg yolk, vanilla and 1-2tsp ice-cold water and pulse/mix until the pastry begins to clump together. Tip on to a work surface, shape into a flattish rectangle, wrap and chill for 30min. Cover egg white and set aside until needed.
  3. Step 3Lightly dust a large sheet of baking parchment with flour and place pastry in the centre. Dust pastry with more flour, top with a second large sheet of parchment and roll pastry into a rectangle large enough to line a 12.5 x 35.5cm rectangular, fluted, loose-bottomed tart tin (see GH TIP). Peel off top parchment then quickly invert pastry on to tin and gently ease it in with your fingers, pressing into the fluted sides. Trim excess and prick base all over with a fork. Chill for 1hr, until very firm.
  4. Step 4Preheat oven to 190°C (170°C fan) mark 5. Line pastry with a large sheet of baking parchment and fill with baking beans. Bake for 25min, or until pastry sides are set and lightly golden. Carefully lift out parchment and beans and return tin to the oven for 5-10min, or until the pastry base feels sandy to the touch. Gently brush the inside of the pastry case with some of the reserved egg white and return to oven for 5min, to set. Set aside to cool.
  5. Step 5Meanwhile, prepare the filling. Soak the gelatine in cold water for 5min. In a medium pan, heat the milk until steaming. In a heatproof bowl, whisk the egg yolks, sugar and flour until combined. Gradually whisk in the hot milk. 
  6. Step 6Pour mixture back into the pan and return to medium heat. Cook for 2-3min, whisking constantly, until thickened and smooth. Remove from heat. Lift out the gelatine (squeeze out excess water), then whisk into the hot milk mixture until dissolved. Whisk in the pistachio butter/paste, until combined. Lay baking parchment or clingfilm on the surface to stop a skin forming and set aside to cool to room temperature (but not set). 
  7. Step 7Scrape the pistachio custard into the pastry case and gently shake tin a few times to level. Chill for at least 2hr (up to 24hr, see GET AHEAD), until set.
  8. Step 8To serve, transfer the tart to a serving plate or board. Top with raspberries and scatter over the pistachios. Lightly dust with icing sugar and serve.