Peel the beans. Press the beans with a spatula through a fine strain to get the smoothest texture.
Transfer the paste to a pan. Add sugar and use low heat to simmer the exceeded water out. Keep stirring. As the paste is heated and sugar is dissolved, the paste will become loose. Add rice syrup and continue stirring all around so that steam gets out and the paste thickens again. Continue cooking until water has evaporated. About 10 minutes.
Turn off the heat, allow paste to cool down. Flatten paste and wrap tightly in plastic wrap. it will thicken slightly as it cools.
When you're ready to use the paste, divide the paste, add in superjuice powder and mix well. (if the paste is too dry, add a little more rice syrup) the Fill the piping bag with bean paste and pipe on the cooled cupcakes. Enjoy!