Red velvet cake is traditionally a red, red-brown, crimson or scarlet-colored chocolate layer cake, layered with ermine icing. Traditional recipes do not use food coloring, with the red color due to non-Dutched, anthocyanin-rich cocoa.

Common ingredients include buttermilk, butter, cocoa, vinegar, and flour. Beetroot or red food coloring may be used for the color.

In addition to the many variations of red velvet cake, there are various red velvet-flavored products, including protein powder, tea, lattes, Pop-Tarts, waffles, and alcoholic beverages. The scent is used for candles and air fresheners as well. For dietary restrictions, such as those due to allergies and ingredient sensitivity, vegan, gluten free, and dairy free variations are available.

Velvet cake is thought to have originated in Maryland early in the 20th century. Beginning in the 19th century, "velvet" cake, a soft and velvety crumb cake, came to be served as a fancy dessert, in contrast to what had been the more common, coarser-crumbed cake. At around the same time, devil's food cake was introduced, which is how some believe that red velvet cake came about. The difference between the two cakes is that devil's food cake uses chocolate and red velvet cake uses cocoa.

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