Rinse the Adzuki Beans: Rinse 240g adzuki beans under cold running tap water. Drain well.Pressure Cook the Adzuki Beans: Place rinsed adzuki beans and 5 cups of cold running tap water into the pressure cooker. Close lid and cook at High Pressure for 20 minutes. Turn off the heat and Natural Release for 15 minutes. Manually release the remaining pressure by carefully turning the venting knob to the venting position. Open the lid carefully.Thicken & Sweeten the Adzuki Beans Mixture: Turn heat to medium (Instant Pot: Press sauté button). Add 2.5 – 3.5 pieces of brown rock sugar into the pressure cooker depending on your preference (see notes). Let the sugar melt and the mixture boil for roughly 10 minutes. Stir occasionally. Mix in 200 ml coconut milk and give it a final taste test. It is normal to taste overly sweet, as freezing will dramatically reduce the sweetness. Mix the cornstarch with water and mix it into the adzuki beans mixture one third at a time. Turn off the heat.Cool & Freeze the Adzuki Beans Coconut Popsicles: Let the adzuki beans mixture cool down completely in a large mixing bowl (see note) and fill the Popsicle molds. Place into freezer for roughly 6 hours before serving!Serve: Run the frozen popsicles under cold running tap water for easier removal of the mold. Enjoy!