Step 1

Preheat the oven to 180C / 350F / 160C fan forced. Line the base of a 9 inch fluted tart tin with removable base with baking paper.

Step 2

Blitz the pistachios in a blender or food processor until very fine (the largest pieces should be only 1mm round)

Step 3

Add the pistachios, flour, sugar and salt to the food processor and blitz until well combined. Add the butter and blitz for only 5-10 seconds until the mixture is like large breadcrumbs. Slowly drizzle in the water while the processor is running on low and stop as soon as it starts forming large clumps.

Step 4

Tip the dough out onto a piece of baking paper and use the paper to help you pull it together into a flat disk. Wrap in the baking paper and place in the fridge for ½ an hour.

Step 5

Dust a large sheet of baking paper with flour and sit the dough on top. Dust the top of the dough with flour, then roll the out to a large circle about 3mm thick.

Step 6

Rest your whole arm underneath the pastry and baking paper to lift it. With the other hand hold the tin and base together with one finger and thumb and tip it upside down over the pastry as you flip the pastry towards it, then flip it back up the right way. Carefully pull away the baking paper, then gently nudge the pastry down into the corners. Trim the overhang with a pair of kitchen scissors to just 1 cm above the lip of the tin and make the dough sit up straight.

Step 7

Freeze for 15 minutes. Prick the base all over with a fork, then line with baking paper and baking weights

Step 8

Bake for 20 minutes. Gather up the corners of the paper and transfer it with the pastry weights to a heatproof dish. Use a sharp knife, laid flat to the top of the tin, to cut away the excess pastry. Brush the inside of the tart shell with beaten egg white all over the base and sides. Bake for a further 20 minutes. Any hairline cracks are fine.

Step 9

As soon as the tin is cool enough to handle, place the shell in the freezer until cold - this will help the panna cotta set more quickly and reduce the risk of leaking or soaking into the base anywhere.

Step 10

Pour the cold milk into a saucepan and sprinkle the gelatine over the top. Allow it to "bloom" for 5 minutes (it should look a bit wrinkly by the end). Turn the heat on low under the milk and stir for a minute or two until the gelatine has dissolved.

Step 11

Add the sugar and stir again until dissolved. This should only take another minute or two. Don't let the milk get too hot or to come to a simmer. It should only be just warm.

Step 12

Take the saucepan off the heat. Pour in the cream, rose water essence (a little at a time to taste- notes) and salt and mix until thoroughly combined.

Step 13

Pour just ½ a cup into the frozen tart shell and swirl around so the bottom is coated. Return to the freezer for 10 minutes. Pour in the remaining panna cotta mixture and place flat in the fridge to set for at least 2 hours to set.

Step 14

Place the water and sugar into a saucepan and sprinkle over the gelatine. Allow it to sit for a couple of minutes.

Step 15

Heat over low heat and stir until the sugar and gelatine has dissolved. Add the raspberries and rose essence and stir, pressing down on the raspberries until the liquid is pink.

Step 16

Pour the liquid through a strainer into a small jug before gently pouring over the top of the set Panna Cotta.

Step 17

Return to the fridge and allow to set for an hour before serving.