Cut Pumpkin (210 gram) to chunk and steam to soft for about 15 minutes. Mash cooked pumpkin with a fork while it is still hot.
Blend mashed pumpkin, Milk (210 gram), and Caster Sugar (80 gram) till fine paste.
Add Instant Dry Yeast (2 teaspoon) and All-Purpose Flour (300 gram) into pumpkin mixture, fold well a hand whisk or rubber spatula to form a smooth dough.
Pour batter into a round lined pan, grease an 8 inch round pan sides and let it rest to double volume, about 20-30 minutes, add Raisins (to taste) on top and place it in steaming wok.
Turn the fire to high and bring water to boil and steam pumpkin cake for 30 minutes. Off heat and let pumpkin cake sit inside the steaming wok for another 5-10 minutes.
Remove cake from pan after slightly cool down. Serve and enjoy!