Rinse the glutinous rice under cold water until the water runs clear.

Soak the rice in water for about 4 hours or overnight.

In a large pot, combine the soaked rice and 2 cups of water. Bring to a boil, reduce to low heat, cover, and simmer for about 25 minutes.

In a mixing bowl, combine the mashed ube, coconut milk, sugar, salt, and vanilla extract.

Once the rice is cooked, gently fold it into the ube mixture until well combined.

Grease a 9x9-inch baking dish and spread the rice mixture evenly.

Set up a steamer or bamboo basket and place the baking dish inside. Steam for about 20 minutes until heated through and firm.

Let the biko cool completely before slicing into squares.