Ingredients

• 320 g all-butter puff pastryall-butter, ready-rolled
• 1 large onioncooked until almost jammy, then cooled
• 20 g butter
• 1 tsp brown sugar
• 1 tsp balsamic vinegar
• 120 g mature cheddarfinely grated
• 1 tsp thyme leaves
• 1 eggbeaten
• 1/4 tsp freshly ground black pepper

Method

1. 01

   Caramelise and cool the onion

   Cook the very thinly sliced onion in the butter with a pinch of salt over medium-low heat for 18-20 minutes, until deep golden. Add the brown sugar and 1 tsp balsamic and cook for 2 minutes more until jammy. Spread on a plate and cool completely. Warm onion melts the butter in the pastry on contact.

   20 g butter · 1 tsp brown sugar

   Cool the onions completelyAny warmth melts the butter between the layers before the oven turns it to steam.

2. 02

   Fill the pastry

   Heat the oven to 200 C / 180 C fan. Unroll the 320 g pastry and scatter half of it with two thirds of the 120 g cheddar, then the thinnest possible smear of onion, a scraped layer you can almost see through, then the 1 tsp thyme and the black pepper. If it looks generous, it is too much.

   320 g all-butter puff pastry · 120 g mature cheddar · 1/4 tsp freshly ground black pepper

   A smear, not a spoonfulHeavy filling weighs the pastry down and the layers never lift. Almost translucent.

3. 03

   Fold and chill

   Fold the bare half over the filling and press gently to seal. Chill for 10 minutes if the pastry has softened at all; cold pastry cuts cleanly and puffs higher.

4. 04

   Cut and twist

   Cut into narrow strips about 2 cm wide and twist each one three or four times, pressing the ends onto a lined tray so they cannot unwind.

5. 05

   Bake

   Brush with the beaten egg, scatter with the remaining cheddar and bake for 18-25 minutes, until dramatically puffed, crisp and dark golden all the way to the centre of the twist. Pale twists are doughy inside.

6. 06

   Cool briefly

   Cool on the tray for 5 minutes so the cheese sets and they firm up enough to lift without bending.