Sami Tamimi and Tara Wigley's sumac onion & herb oil buns

1 Put the flour, sugar and yeast into the bowl of a freestanding mixer, with the dough hook in place. Mix on a low speed for 1 minute. Whisk together the eggs and 120ml water and add these to the mixer. Work on a low speed for a few seconds, then increase the speed to medium. Continue to work for 2 minutes, until the dough comes together. Add ½ tsp salt then start adding the butter, a few cubes at a time, until it melts together into the dough. Continue kneading for about 10 minutes, on a medium speed, until the dough is completely smooth, elastic and shiny. Place the dough in a large bowl brushed with sunflower oil, cover with a clean tea towel and leave in the fridge for at least half a day, or preferably overnight. It will increase in volume by just under 50%.

2 To make the filling, put 3 tbsp oil into a medium sauté pan and place on a medium-low heat. Add the onions and cook for 15 minutes, stirring frequently, until they are completely soft and golden brown. Add the cinnamon and cook for another minute. Remove from the heat and set aside to cool before adding the remaining 55ml olive oil, the sumac, oregano, thyme, sugar and salt.

3 Grease and line a 20x30cm baking tray. On a lightly floured surface, roll the dough out into a rectangle, about 55x35cm. Spread the sumac onion mixture all over the dough, taking it right up to the edges.

4 With the long end facing towards you, gently roll up the dough as you would a Swiss roll, using both hands to gently press and roll as you go along. Trim about 2cm off both ends so that it becomes a perfect sausage. Then cut the sausage widthways into 12 even slices, each about 4cm wide. Carefully arrange the slices on the baking tray, evenly spaced apart and cutsides facing up so the filling is showing. Cover the tin with a slightly damp tea towel and leave to rise in a warm place (near a stove, for example) for 1½ hours. The rolls will rise by 20-30 per cent.

5 About 30 minutes before the buns have finished rising, preheat the oven to 180℃ fan.

6 Remove the tea towel and place the tray of buns on the middle shelf of the oven. Cook for 30 minutes, until the buns are golden brown. Remove from the oven, cover loosely with foil and return the buns to the oven for about another 20 minutes, or until the dough is cooked through.

7 Remove the buns from the oven and set aside to cool for half an hour while you combine all the ingredients for the herb oil in a bowl with a small pinch of salt. Once the buns have cooled, pour this evenly over the top. Sprinkle lightly with sumac and serve.