Red Onion and Parmesan Tarts

1. To make the pastry, put the flour and butter into a food processor and whiz until the mixture resembles breadcrumbs. Tip into a bowl and add the salt, egg yolk and 7 tsp cold water. Mix well and bring the dough together with your hands. Wrap in Saran wrap and rest in the fridge for 15 minutes.

2. To make the filling, cut the onions into fine wedges and toss in the lemon juice. Melt the butter with the olive oil in a skillet. Add the onions and saute gently for 15 minutes. Put to one side.

3. Divide the pastry into six. Roll out each piece on a lightly floured surface and use to line six greased 11 cm (4 1/2 inch) loose-based individual tart tins. Prick the bases with a fork. Put on a lipped baking sheet, cover with Saran wrap and leave to rest in the fridge for 20 minutes.

4. Line the tart tins with greaseproof paper and baking beans and bake at 200°C (180°C fan oven) for 10 - 15 minutes. Remove the paper and beans and return to the oven for 5 minutes to dry the pastry bases.

5. Increase the oven temperature to 230°C (210°C fan oven) mark 8. Mix the creme fraiche and thyme together in a bowl and season with salt and pepper.

6. Divide half the onions among the pastry cases, spoon over half the creme fraiche and sprinkle with half the Parmesan. Top with the rest of the onions, creme fraiche and Parmesan. Bake for 5 - 10 minutes or until golden. Serve garnished with thyme.