Tangzhong is a cooking method used in bread-making that involves creating a roux by cooking flour and water together. This mixture is heated until it thickens, usually to a temperature of around 65°C (149°F). The purpose of Tangzhong is to improve the texture and moisture retention of the bread, resulting in a softer and fluffier loaf. When added to the dough, Tangzhong helps to enhance the bread's shelf life by keeping it fresh for longer periods. This technique is commonly used in Asian bread recipes, particularly in Japanese and Chinese baking, where soft, pillowy bread is highly desired.