First, make the pastry. Sift the flour and
salt together into a food processor or a
large bowl if you want to make it by hand.
Pulse or rub in the butter until it resembles
breadcrumbs. Add enough water to make
the dough come together, then wrap well
and chill in the fridge for 10-15 mins.
Roll out the pastry on a lightly floured
surface until just thinner than a £1 coin
then line a 26cm tart tin – don’t trim off
the excess pastry just yet though, as
it will shrink a little when it cooks.
Heat oven to 200C/180C fan/gas 6.
Remove the pastry case from the fridge
and line with baking parchment.
Fill with baking beans, then bake blind for
20 mins. Remove beans and paper then
cook for 5 mins more until pale golden.
Turn down the oven to 160C/140C fan/
gas 3. Trim the edges of the pastry case
with a sharp serrated knife.
Arrange the watercress and salmon in
the bottom of the pastry case. Whisk the
dill, eggs, milk and cream and season
well. Pour over the salmon and watercress
then bake for 30-40 mins, or until set
with a slight wobble in the centre.
Serve warm, or at room temperature.