Steamed Banana Cake (banh chuoi hap)

This recipe is from the most southern part of Vietnam. I remember that people sold this sweet dish at every gas station or bus stop in Vietnam. The sweet-scented chewy layer of banana, covered with creamy coconut milk, topped with fragrant roasted sesame seeds make this dish a cool desert.
Ingredients:
7 oz tapioca starch
1 oz rice flour
3/4 cup water
2 drops of yellow food color
Syrup:
1/2 cup sugar
1 cup water

Filling:
5 bananas
Garnish with coconut milk and roasted sesame seeds
Directions:
In a saucepan, bring the syrup to a boil.
Mix the tapioca with 1/2 cup water and pour the hot syrup into the tapioca mix. This process will partially cook the tapioca flour so that the steamed flour will not stick to the bottom.

Slice bananas into 1-inch thick pieces.
Cover the round cake pan with plastic wrap. Layer banana slices on the bottom of the pan.

Pour the flour mixture on top. Now there is one layer of banana and the flour on the cake pan.

Steam over high heat until the flour looks clear.
Repeat another layer of bananas and flour. Put them back to steamer and cover with a kitchen towel to absorb some of water while steaming.

Continue until it is done. Let the whole cake cook for 1 hour. The cake is cooked when an inserted toothpick comes out clean. Let the cake completely cool before serving.