Cut butter into cubes and rub into flour with your fingertips until mixture resembles coarse breadcrumbs.

Add egg yolk and enough water to just bring the dough together so it holds.

Work the pastry into a ball, wrap in plastic wrap and chill in the fridge for at least one hour.

On a floured surface roll dough out slightly larger than your tart tin. Trim pastry slightly above the edge of the tin to allow for shrinkage during cooking. Freeze the case or chill well until you are ready to bake.

Use baking paper and pie weights to weigh down the tart case as it bakes. Bake at 180ºC for 10-15 minutes then remove weights and bake for a further 5-10 minutes until the shell is golden. Cool and set aside.

Poach the pears:

Bring sugar and water to the boil in a saucepan with the vanilla bean (split lengthwise and seeds scraped into water) and lemon rind. Put pear halves into the syrup, add lemon juice, cover with a square of greaseproof paper to keep the pears submerged, and put the lid on the saucepan. Simmer until pears are just soft, about 15 minutes, then remove from the syrup and chill. The pears, returned to the cold syrup, can be kept in the fridge for a few days.

Assemble the tart:

Slice each poached pear half into three pieces and arrange in the prepared pastry case.

To make the filling: Whisk together the sugar and eggs until lightened in colour, then whisk in the flour, cardamom and a pinch of salt.

Brown the butter in a small saucepan over a low heat until dark brown. Remove from heat and allow to cool slightly, then whisk into the egg mixture while still warm. Pour this filling over the tart as soon as possible and bake at 175ºC for about 45 minutes. The filling should be close to fully set before being removed from the oven.

Serve warm or cool with a dollop of whipped cream or a scoop of vanilla ice-cream.