Soft, golden brioche buns, egg-washed and topped with sesame. Fluffy, yet sturdy enough to hold a proper burger without falling apart.
Dissolve the yeast in the warm milk and let it rest for 10 minutes.
Mix the flour, sugars and salt together in a bowl.
Add the yeast mixture, then the egg and egg yolks, and mix for about 10 minutes, adding the butter gradually as you go.
Add a little extra flour if needed, until the dough is smooth and no longer sticking heavily to the sides of the bowl.
Put the dough in a lightly buttered bowl and let it rise for an hour somewhere warm.
Knead the dough briefly and divide into 6 or 8 buns. Arrange on a baking sheet and let rest, covered, for another hour.
Whisk the extra egg yolk with a splash of milk and brush evenly over the buns, then top with sesame seeds.
Bake at 190°C fan for about 12 minutes, until golden brown.
Add the butter slowly while mixing, piece by piece. Brioche dough only comes together properly if the fat goes in gradually, not all at once.