A dough starter, commonly known as a “sourdough starter” or “levain,” is a mixture of flour and water that captures wild yeast and bacteria from the environment. It serves as a natural leavening agent for bread. To create a sourdough starter, one typically combines equal parts of flour and water and allows the mixture to ferment over several days. During this fermentation process, wild yeast and lactic acid bacteria naturally present in the environment colonize the mixture, creating a living culture. This starter is then incorporated into bread recipes to provide leavening, contributing to the unique flavor, texture, and rise associated with sourdough bread. Regular feeding and maintenance of the starter help keep it active and healthy for continued bread-making.