To make the pastry
Sift the flour and icing sugar together in a food processor. Add the butter and pulse until the mixture resembles breadcrumbs.
Mix in the egg and pulse gently until the dough just comes together. Turn out onto a lightly floured surface, knead gently, then flatten into a round.
Wrap in clingfilm and chill in the fridge for 30 minutes.
Preheat the oven to 180C/Gas Mark 4 and roll out the pastry on a lightly floured surface to a 3-4mm thickness and use to line 4 individual flan tins of 7.5cm in diameter and 2.5cm deep, then trim the edges.
Place in the fridge to rest for 15 minutes before baking.
Remove from the fridge and add some parchment paper and a layer of baking beans to each tin.
Bake in the pre-heated oven for 10 minutes, then remove the beans and paper and cook for another 10 minutes or until golden.
While the pastry is still warm, brush the inside with the beaten egg yolk as this helps to seal the pastry from the tart filling and ensures a crispy base.
To make the strawberry filling
Once the pastry is baked and cooled, fill the base of the pasty with whipped cream.
Remove the stalks from the strawberries and cut into quarters.
Place on top of the whipped cream.
Meanwhile in a pan, heat the strawberry jam until it thins.
Pass the jam through a sieve to remove any seeds.
Brush the strawberry jam mixture over the strawberries then garnish with lemon thyme leaves. Sprinkle with cracked black pepper.