1.To make mochi batter: in a mixing bowl, combine glutinous rice flour, sugar, and coconut milk. Add water gradually and mix well.
2.The batter should be somewhat liquid. Add the oil at the end and mix well with the rest. Transfer the batter to a heat resistant container and steam it for 20 – 25 minutes over medium-high heat.
3.While waiting for the glutinous rice, shape the red bean paste into 1 inch diameter balls. These will be the filling.
4.Check the steamed rice mixture with a stick or chop stick. It should be completely solid. Cool it down for about 8 minutes until you can handle it by hands. Do not let it cool down to room temperature.
5.Take 1 tbsp of rice cake and cover it in plastic wrap on both sides. Slightly press the cake to flatten it out.
6.Place the bean paste ball filling in the middle of the flat cake. Carefully wrap the rice cake around the filling.
7.As you fold the cake to wrap the filling and close the opening, make sure you shape the rice cake in a ball.
8.Dust the mochi with powdered sugar thoroughly.