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The most common mistakes made by home bakers, professionals say, have to do with the care and handling of one ingredient: butter. Creaming butter correctly, keeping butter doughs cold, and starting with fresh, good-tasting butter are vital details that professionals take for granted, and home bakers often miss.

Butter is basically an emulsion of water in fat, with some dairy solids that help hold them together. But food scientists, chefs and dairy professionals stress butter