Place the flour in a large bowl and rub in the butter until the mixture resembles breadcrumbs.
Add the salt, sugar and egg and bring together to form a dough.
You may need to add a little water. Wrap the dough in cling film and chill for 30 minutes.
Preheat the oven to 180°C (160º fan) 375ºF, gas 5. Put the Roquefort into a small bowl and mash with a fork.
Add the eggs, sour cream and yoghurt and mix well. Season to taste with pepper.
Butter 4 small quiche dishes and dust with flour.
Roll out the pastry on a floured work surface and cut out 4 circles to fit the quiche dishes using the quiche dishes as a guide.
Line the dishes with the pastry and prick the bases with a fork.
Arrange the pear slices neatly in the pastry cases and pour the Roquefort mixture over them.
Bake in the preheated oven for 20–25 minutes, or until done. Garnish with herbs of your choice and serve warm or lukewarm.