Pre heat oven 200C. Line a baking tray with baking paper.
Mix yeast, warm water and sugar leave for 10 minutes.
Separate eggs. Melt butter. Sift flour, add salt, then yeast mix, then butter and egg yolks lightly whisked. Knead for 10 minutes. Put into a lightly floured bowl until doubled in size. Cut into 8 rounds and put on a greased tray for 1 hour, then brush with egg wash. Add sesame seeds. Cook in oven for 15-20 minutes or until lightly golden.