heaping cups of all-purpose flour

All-purpose flour is a refined wheat flour milled from a blend of hard and soft wheat varieties, producing a product with moderate protein content (approximately 10-12%) suitable for a wide range of baking and cooking applications. The wheat grain is processed by removing the bran and germ, leaving primarily the endosperm, which is then ground to a fine powder. All-purpose flour is the most versatile flour in Western baking, designed to perform adequately in both yeast breads and tender cakes, though it does not excel equally in all applications. The flour is often bleached with chemical agents to whiten it and improve baking properties, though unbleached versions are also widely available.

All-purpose flour is the standard thickening agent and structural foundation in Western baking and cooking. It is used to produce breads, cakes, cookies, pastries, biscuits, and quick breads, as well as in sauce-making (roux), batters, and breading. The moderate protein content makes it a compromise ingredient—adequate for developing gluten structure in bread yet tender enough for cakes and pastries. It also serves as a dusting agent for work surfaces and a thickener for gravies and soups across numerous culinary traditions.