1) Fill the bottom pan of a steamer with water, cover and let it heat.
2) In a large bowl, mix together the rice flour, wheat strach, cornstarch, oil and salt. Ensure that the batter does not have any lumps.
3) Line a baking dish with parchment paper or cheesecloth.
4) Pour the thin layer of batter into the dish, just enough to cover the surface, and add some of the filling ingredients.
5) Steam for about 3 minutes, or till set, over the boiling water while still on high heat.
6) Remove the rice layer with filling from the dish and set it on a work surface that has been brushed with some oil.
7) Roll the steamed rice flour layer. Now, you can either slice the roll or keep it as it is.
8) Repeat the steps from cooking to roll the rice flour out till all the batter and filling has been used up.
9) To make the sauce, simple put all the ingredients for the sauce in a pan and let it gently come to a boil.
10) Serve the Cheong Fun right away, while it is still fresh with the sauce on the side.