For the pre-ferment
400g/14oz Canadian very strong bread flour
1g/?oz fast-action bread yeast
400g/14oz cold water
For the dough
700g/1lb 8?oz pre-fermented batter
200g/7oz free-range egg yolks (approximately 10 eggs)
60g/2?oz water at 20C
400g/14oz Canadian very strong bread flour
100g/3?oz unrefined caster sugar
70g/2?oz skimmed milk powder
15g/?oz table salt
14g/?oz fast-action yeast (2 sachets)
60g/2?oz browned butter, strained and at room temperature
30g/1oz grapeseed oil
35g/1?oz Trex, at room temperature (available at supermarkets, Trex is a vegetable fat used for pastry and bread)
For the egg wash
50g/1?oz whole free-range eggs
20g/?oz free-range egg yolks
dash water
pinch salt
sesame seeds, as needed
Method
You will need the following special equipment: food mixer with dough hook, very coarse sieve, meat grinder, large cast-iron pan, digital probe.
PREPARING THE PRE-FERMENT
1. Tip the flour into your mixing bowl and add the yeast.
2. Using a dough hook, begin mixing on low speed and gradually pour in the water until it has all been added.
3. Continue mixing on medium speed until a very liquid batter has formed.
4. Pour this batter into a clean, dry container (at least four times bigger than the volume of the batter). Cover and leave in a cool place for 24 hours to ferment.
MAKING THE DOUGH
1. After 24 hours, weigh out 700g/1lb 8?oz of pre-fermented batter and put it in a mixing bowl with a dough hook attachment. Add the egg yolks and the water and begin mixing on a low speed until the dough is homogeneous and very liquid again (approximately two minutes).
2. Sift the flour, sugar, skimmed milk powder, salt and yeast into a separate bowl through a very coarse sieve (this will help prevent them forming lumps when added to the dough). Stir to combine. If a suitable sieve isn't available, simply stir the ingredients together.
3. Gradually add the sifted ingredients to the dough while continuing to mix on slow speed. Once all have been added, increase the speed to medium and mix for another 2-3 minutes. The dough will look very sticky and wet.
4. Brown the butter in a pan until it develops a very nutty aroma, then strain it and discard the butter solids.
5. Add the browned butter, grapeseed oil and Trex to the dough and continue to mix for another 3-4 minutes, until well combined.
6. Stop the mixer and let the dough sit for ten minutes to absorb the water, then continue to mix on medium speed for another four minutes.
7. Cover the dough and place in the fridge for 30 minutes to firm up.
8. In the meantime, cut a piece of baking parchment to fit a large baking sheet.
9. Cut eight sheets of aluminium foil 50cm/20in long. Fold the sheets of foil in half in the shorter direction, then continue to fold in half until you have an aluminum strip 1cm/?in wide and 50cm/20in long. Tape one end of the strip to the other with a bit of overlap to form a ring approximately 12cm/5in in diameter. Repeat this process with the other sheets of foil.
10. When the dough has chilled, weigh out eight 85g/3oz portions. Any remaining dough can be wrapped up and frozen to use another time.
11. Lightly flour your hands and quickly roll each piece of dough into a small ball using the palm of your hand. Place the balls on the prepared baking sheet and place a foil ring around each one.
12. With wet hands, lightly pat the balls flat, then cover the baking sheet with cling film to prevent the dough from drying out.
13. Set the dough aside in a warm place (between 18-22C), for 1?-2 hours to let it prove.
14. When ready to bake, preheat the oven to 225C/425F/Gas 7, and mix all the ingredients for the egg wash except the sesame seeds.
15. Using wet hands, lightly flatten the dough balls within the foil rings.
16. Just before baking, pour some water into a tray and place at the bottom of the oven to make it lightly steamy. (This will prevent the buns from cracking on the surface and developing too thick a crust).
17. Bake the buns for seven minutes, then remove from the oven and brush the tops with the egg wash. Generously cover each one with sesame seeds.
18. Return to the oven for a further seven minutes, or until the buns are done. Remove and place on a wire rack to cool.
