Step 1

Snap the brown sugar slabs in half and add them to a saucepan. Pour 2 1/2 cups of water over the sugar slabs and bring the water to boil. Continue simmering the liquid until the sugar slabs dissolve completely. If you’re using light brown sugar, add it to the saucepan, along with 2 1/2 cups of water. Bring the water to boil and turn off the heat. The sugar should dissolve once the water boils.

Step 2

Add the tapioca flour and 1 1/2 cups of room temperature water to a mixing bowl. Try to stir the flour and water together. The flour at the bottom of the bowl will feel very stiff and that’s okay. Stop stirring if it feels like the flour is stuck.

Step 3

Once the brown sugar has dissolved, turn off the heat. Pour 1/3 of the hot sugar liquid into the bowl with the tapioca flour slurry and stir. The batter should be much easier to mix now. Pour the remainder of the brown sugar liquid into the bowl and mix again. Make sure to use your wooden spoon or spatula to scrape the bottom of the mixing bowl to ensure that there are no clumps of flour stuck there.

Step 4

Add a steaming rack into the center of a large wok. Fill the wok with water, until there’s about a 1/2-inch gap between the water level and the top of the steaming rack. Cover the wok and bring the water to boil.

Step 5

Lightly grease the pan with any neutral oil (such as vegetable oil). Once the water boils, carefully place the greased pan over the steaming rack. Reduce the heat to medium.

Step 6

Give the batter a stir because the tapioca flour sinks to the bottom of the bowl within minutes. Pour 2/3 cup of batter into the pan. The batter should cover the bottom of the pan completely. If it doesn’t, pour more batter into the pan. Cover the wok with a lid and steam for 4 minutes over medium heat.

Step 7

Uncover the pan. Make sure the layer is completely translucent and you can see the bottom of the pan. This is an indication that the batter is fully cooked. Pour another 2/3 cup of batter into the pan, cover the wok with a lid, and steam for another 4 minutes.

Step 8

Continue steaming the cake layer by layer, giving the batter a stir before adding 2/3 cup of it into the pan. Again, the batter should cover the entire surface of the pan. If it doesn’t, add more. Layers 3 to 5 will take about 5 minutes to steam, and layers 7 to 9 will take about 6 minutes. As the cake gets thicker, the latter layers will take longer to turn translucent. If at any point, the cake looks opaque, do not add more batter to the pan. Make sure the layer turns translucent completely. Otherwise, the opaque layer will stay that way even if you continue steaming the cake. (See blog post for more in-depth explanation.) Replenish the water in the wok when you get to about layer 5, as the water evaporates over time.

Step 9

Once all the layers have been steamed, turn off the heat. There will likely be a lot of water over the top layer, which is due to the condensation that develops inside the wok. Holding on to the pan with dry towels or oven mitts, carefully tip the pan and drain the water. Be careful because the cake can slide around.

Step 10

Sprinkle some toasted sesame seeds and coconut over the top of the cake for garnish. It’s better to sprinkle the toppings while the cake is still warm to ensure that they stick onto the cake.

Step 11

Let the cake cool completely before slicing and serving.

Step 12

There are several ways to cut into the cake. The easiest thing to do is to run a silicone spatula along the edge of the pan to loosen the cake. Then, use kitchen scissors to cut the cake into pieces.

Step 13

Alternatively, you can cut the cake on a chopping board. Don’t cut the cake over a wooden or bamboo board, as the cake will stick to the board and be difficult to pry off. I typically grease a marble slab and cut the cake over that. You can also use a grease silicone chopping mat. Make sure to grease the knife with oil frequently. Interestingly, you don’t need to grease the kitchen scissors when cutting the cake.

Step 14

You can leave the cake on your counter, covered, overnight. The cake usually keeps well, provided that your kitchen isn’t hot and humid. If you’re storing it for more than a day, you’ll want to refrigerate the cake. You can reheat the cake again by steaming it for several minutes or microwaving it until the cake softens.

Step 15

Eat the cake within 3 or 4 days because mold will start to form on the cake. You can freeze the cake for longer storage and steam the cake to reheat.