Lucas Hollweg’s Onion Tart with Thyme and Parmesan

Serves 6-8

  • 1 quantity plain shortcrust pastry (page 260)
  • 75g (2¾oz) butter
  • 4 medium onions, peeled and thinly sliced
  • salt and pepper
  • 5 bushy sprigs of thyme
  • 4 tbsp dry white wine
  • 300g (10½oz) double cream
  • 1 whole medium egg and 3 medium egg yolks
  • 25g (1oz) Parmesan
  1. Melt the butter in a large saucepan. Add the sliced onions, a pinch of salt and the leaves from 3 sprigs of thyme. Stir everything together, then cover with a lid and cook over a gentle heat for 45 minutes, or until the onions are soft and squidgy, but not in any way brown. You might want to give them a stir from time to time. Add the wine and bubble away, without a lid, for 10 minutes, or until the liquid has mostly evaporated. Remove from the heat and keep to one side.
  2. On a floured surface, roll out the pastry to about the thickness of a £1 coin.
  3. You want it big enough to line a round 23cm (9in), loose-bottomed tart tin, allowing for the depth as well as the width. Carefully roll half the pastry around your rolling pin, then lift it into the tin. Ease it into the base and corners, pressing together any splits and patching any holes with offcuts, then trim it so that it overhangs the top by a finger’s width. Prick the bottom all over with a fork, then line the base and sides with a circle of baking parchment and put in the fridge for 30 minutes. Put a flat baking sheet in the oven and preheat it to 190°C/375°F/Gas Mark 5.
  4. Fill the baking parchment liner with ceramic baking beans, uncooked pasta shapes, dried beans or rice. Put the tart tin on the preheated baking sheet in the oven and bake for 10 minutes, or until the sides have set. Remove the parchment and beans, then turn down the oven to 180°C/350°F/Gas Mark 4 and put the tart back in for 10–15 minutes, or until the bottom of the shell feels dry and is the palest golden brown. Remove from the oven and trim the top with a serrated knife. Leave the oven on. In a mixing bowl, beat together the cream, egg and yolks. Keep back about 1 tablespoon of the Parmesan and stir the rest into the cream. Season well, particularly with salt, then stir in the onion mixture until everything is well combined.
  5. Pour into the tart, smoothing the top, and scatter with the remaining Parmesan and thyme leaves. Put in the oven and bake for 30 minutes, or until the filling is puffed and golden and just set in the middle. Leave to cool in the tin for 15 minutes before carefully unmoulding. Eat while it’s still warm.

Credits

This recipe was produced with kind permission of Collins publishing.