Evaporated milk lends the cake a rich, lightly malted flavor, though an equal amount of whole milk can be substituted for a lighter taste. When measuring flour, we spoon it into a dry measuring cup and level off excess. (Scooping directly from the bag compacts the flour, resulting in dry baked goods.) Custard powder gives Ma Lai Gao its signature bouncy texture; it can be found online or substitute vanilla pudding mix. You can also steam the cake in an 8-inch metal cake pan lined with parchment and greased with nonstick spray. You will need a 6-inch metal steamer rack (at least 1 inch high) to lift the cake pan from the water, which can be purchased online or in the cookware aisle of your Asian supermarket.