Lightly grease a long, fluted, loose-based tart tin, the one pictured measures 35 x 12.5 cm, though you could use a 26cm round tin. To make the pastry, place the butter, flour, ground nuts, sugar and salt in the bowl of a food processor with the blades attached. Pulse until the mixture looks like rough breadcrumbs, then pour in the whole, beaten egg and continue to pulse until the mixture begins to clump together.

Scrape the mixture out onto a floured benchtop and lightly knead until it forms a smooth dough. Keeping the dough and the benchtop well floured, roll the dough out to fit the shape of the tin you are using, then use the rolling pin to lift the dough into the tin. Press the dough carefully into all corners, taking care to patch anywhere it may have torn. Roll the rolling pin across the top of the tin to trim the edges (reserving any leftover dough), prick all over with a fork, then put the pastry-lined tin into the freezer for 20 minutes. If using ready-made pastry, simply line the tin with the two sheets, trimming to fit, then freeze for 15 minutes before proceeding as below.

Heat the oven to 200°C / 400°F with a rack in the middle shelf. Remove the pastry-lined tin from the freezer, scrunch up a piece of baking paper, then smooth it out and use it to line the pastry, making sure the base and sides are covered. Line this with a layer of tin foil, then weight down with a couple of ramekins (or baking weights if you prefer) then bake in the preheated oven for 20 minutes.

Remove from the oven, carefully lift out the baking paper and foil, check to make sure there are no rips or tears in the pastry - if so, gently use a little of the reserved pastry to patch them up, then return to the oven for another 5-7 minutes, keeping an eye on the pastry as the nuts can brown very quickly.

When the pastry is golden brown and cooked, remove from the oven, allow to cool for 5 minutes, then carefully brush all over with the beaten egg white and set aside to cool completely. This will seal the pastry and prevent the dreaded soggy bottom. The pastry case will keep like this for 3 or 4 days in an airtight container.

When you are ready to make the filling, heat the cream, honey and sugar together in a deep saucepan (see tips and tricks) stirring over medium heat until the sugar has dissolved. Bring to the boil, then turn the heat down to a steady simmer and continue to cook, stirring for 3 minutes. Remove from the heat, stir in the lemon juice until completely combined then set aside to cool for 10 minutes.

Scatter 125g of raspberries over the base of the tart, then strain the creamy filling through a sieve into a large jug. Pour over the raspberries (you may find it easier to already have the tart on the top shelf of the fridge to prevent spills while carrying) until the filling nearly reaches the top of the pastry. Chill in the fridge for at least 3 hours or until completely set. If there is any remaining filling (I always make extra as tart tins are different sizes and depths, and because I consider it a chef treat) pour it into ramekins or small glasses and leave to set in the fridge. It will take a little longer to set as it is deeper.

When the tart has set, remove from the tin, scatter over the remaining raspberries and serve while cold.