Tomato, crème fraîche and mustard tart

Method

1. Preheat the oven to 180°C/350°F/gas mark 4 and lightly grease a 28–30cm loose-bottomed tart case.
2. Put the flour, salt, Parmesan (if using) and butter in a food processor and blend until the mixture resembles fine breadcrumbs. Add cold water, a tablespoon at a time, and pulse bit by bit until the mixture just comes together as a dough. Bring the dough together with your hands and shape into a large flat disc. Clingfilm the pastry and allow it to rest in the fridge for 30 minutes.
3. Dust a rolling pin and surface lightly with flour and roll out the dough to about 5cm larger than the tart case. Lift it up by carefully rolling it around the rolling pin and lay it across the tart case. Press the dough into the corners of the case using your fingers, filling any holes or tears as you go. Trim the pastry edges and chill for 30 minutes.
4. While the pastry chills, toss the tomatoes with a pinch of salt, the butter and half the thyme and arrange cut side up on a baking tray. Roast for 10–15 minutes until they are soft yet retain their shape.
5. Remove from the oven and set to one side to cool, keeping any juices. Fill the pastry case with a circle of baking parchment and baking beans. Bake for 15 minutes, then remove the paper with the beans and cook the pastry for another 5 minutes. Use any uncooked pastry to patch any holes.
6. While the pastry is cooking, beat together the crème fraîche, garlic, mustard, the remaining thyme and salt and pepper to taste. Add any juices from the tomato roasting tray and spread the mixture over the blind baked tart case.
7. Arrange the tomatoes over the top – don’t be precious here. Bake for 20–25 minutes until the pastry is crisp and the tomatoes are golden. Leave the tart to cool in the tin for 15 minutes or so before removing and serving warm.