Rinse the red beans thoroughly and boil them in a pot.
Drain the boiled beans using a strainer to remove excess water.
Blend the cooked beans with low-calorie sweetener and salt using a hand blender until smooth.
Transfer the blended beans to a pan and cook on low heat, stirring to evaporate excess moisture.
Add soy milk and mix well, bringing it to a simmer once more.
When the mixture reaches your preferred consistency, turn off the heat and let it cool.