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A laminated dough produces the distinct flaky layers in the crust that bake up crisp and light.
Including a high proportion of flour in the butter layer and egg yolk in the lean dough layer tenderizes the crust, and creates a delicate texture.
A combination of water and evaporated milk allows the egg flavor to come through in the custard.
Added egg yolks enhance the color and richness of the custard.
Walk around in any Chinatown and you’ll eventually find yourself browsing the display case of a Chinese bakery. These shops offer cakes and snacks that present a departure from traditional European bakery fare: Fluffy coconut cocktail buns (gai mei bao), crackling pineapple buns (bolo bao), mooncakes, and riffs on Western European items like the Hong Kong Sweet Bun (based on the many styles of English cream buns) are just a few examples of the unique pastries that make up Tang bing, or “Tang-style baked goods”.
Perhaps one of the most well-known of these confections—a standard by which all Chinese bakeries may be judged—is the Cantonese or Guangzhou-style egg tart (daan tat). With its silky, sweet egg custard filling encased by crisp and tender puff pastry, this tart is believed to have originated in Canton (now Guangzhou) around the 1920s, in response to the sudden influx of British businessmen and officials and their love of the British egg custard tart. The southern Chinese city was a prominent international port destination dating to the 18th century, and attracted British chefs and bakers who shared many of their recipes—including egg tarts.