Besides flour, yeast is an essential defining ingredient in bread: It's what distinguishes an airy, springy loaf of bread from a dense, unpalatable lump of dough. Unlike other leavenings ...

You can adjust the recipe timings to make this loaf ... yeast and salt together in a large bowl. Add 325ml/11fl oz warm water and scrunch the flour mixture and water together until no lumps ...

Seamus Blackley/TwitterA researcher-slash-baker successfully baked a sourdough loaf from 4,500-year-old yeast. Bread has been a common staple for many cultures around the world since ancient times.