Place all the flour into a machine bowl with the salt, malt extract and butter. Leave for 5-8 minutes before placing the yeast and sugar into a jug together and leave for 5 minutes.
Add the buttermilk and yeasted water, turning the speed up to medium and mix for 6-8 minutes.
Turn to a high speed for four minutes and then turn out and knead for 5 minutes. Leave to prove in a warm place. Prove for approx 90 minutes, then knock back, cutting to 80g weight pieces.
Shape and place on a floured tray. Prove for approx 60-80 minutes, then egg wash with a yolk wash and sprinkle with plenty of sesame seeds.
Bake at 200c for 10-12 minutes, then cool on a wire rack.