Hong Kong Egg Tarts

Name: Hong Kong Egg Tarts
Ingredients: 8 cups (1¾ lb.) cake flour; 4 cups (2 lb.) white vegetable shortening, at room temperature, diced; 3 sticks butter, at room temperature, diced; 1 stick margarine, at room temperature, diced; 7 ½ cups (1⅔ lb.) cake flour; 1 cup bread flour; ½ cup superfine sugar; ½ cup white vegetable shortening, at room temperature, diced; 2 eggs, lightly beaten; 1–2 cups water, for binding; Cake flour, for dusting; Vegetable oil, for oiling; 1¼ cups lightly beaten raw egg; ¾ cup superfine sugar; 2 Tbsp. custard powder; 2½ cups water; 1¼ cups evaporated milk