Tomato & Thyme Palmiers with Cheddar and Chive Mayonnaise

1. Put the puff pastry on a well-floured surface and bash it with a rolling pin.
2. Usually you need to be quite delicate with puff pastry as it needs to puff up a lot, but for palmiers it only needs to puff up a little. Roll the pastry out into a rectangle about 30 x 35cm/12 x 14″ and the thickness of a £1 coin. Spread the tomatoes over the puff pastry and sprinkle over the Thyme. With the shortest end facing you, take both long edges of the pastry and roll them towards each other to meet in the middle. Brush a little egg down the centre to stick the two halves together. Carefully lift into a large baking tray (making sure it will fit in your fridge first) and put in the fridge for at least 30 minutes to chill and harden.
3. Preheat the oven to 200C/400F/Gas 6
4. Remove the roll from the fridge and, using a very sharp knife, slice it into 1cm/1⁄2in thick pieces. Lay each piece on the baking tray, cut-side up, and brush well with the beaten egg, then bake in the oven for 10–15 minutes until puffed up, crisp and golden-brown
5. Remove the palmiers from the oven and leave to cool on the baking tray
6. To serve, pile them high on a plate. Serve with Cheddar Cheese and Chive Mayonnaise

For the Mayonnaise

1. Place the egg yolks into a food processor with the cheese, mustard, vinegar and chives.
2. Blend for 1 minute, then slowly pour in the oil as the processor runs
3. Once all the oil is blended, stop the processor and add a little salt to taste.
4. Remove the mayonnaise from the processor and transfer to a sealable container.
5. Refrigerate until ready to use