Caramelised onion and machecoulais tarte tatin

Peel and slice the onions into 1cm thick rounds.

To make the caramelised onions, heat the olive oil and butter in a 28cm oven-proof pan (preferably a cast-iron pan), over a medium-low heat. When the butter is melted, stir in the dark muscovado sugar and balsamic vinegar. Allow the sugar to melt a bit before adding the onion rounds. Arrange the onion rounds in the pan, to completely cover the base, season with salt and freshly ground black pepper, then scatter over the thyme leaves. Cook the onions over a low heat for 8-10 minutes without moving them, or until they are soft on top and golden at the bottom. They will shrink a little as they cook, so you may be able to fit in a few more as they reduce in size. When the onions are cooked, remove the pan from the heat and allow it to cool for 10 minutes.

Preheat the oven to 200°C, gas mark 6.

Roll out the sheet of puff pastry to a size slightly larger than the pan. Trim any excess pastry. Carefully place the puff pastry over the caramelised onions in the pan, tucking in the edges to encase the onions. Transfer the pan to the oven and bake for approx. 25-30 minutes, or until the puff pastry is golden brown and crispy. Remove the pan from the oven.

Place a large serving platter or plate over the pan. Carefully and quickly flip the pan upside down onto the platter, allowing the tarte tatin to release from the pan onto the plate. Be careful as the caramelised onions will be hot.

While the tarte tatin is still hot, crumble the Machecoulais cheese over the caramelised onions. Sprinkle over the fresh thyme leaves.

Slice the tarte tatin into wedges and serve while still hot.