Measure out COLD soy milk or any other plant-based milk, extract, the flavor of choice, lecithin, sweetener, some tapioca starch, and oil (if desired). Combine all in a sauce pan.
Mix the starch into the milk before turning on the heat.
Turn the heat to medium and stir frequently until it comes to a slow boil.
Let it boil for a few seconds while stirring constantly and then turn off the heat.
Store in an airtight jar or bottle for up to 5 days.
Notes
You can also use coffee syrups to flavor the creamer. For this method, use 2 tbsp of syrup and omit the extract and sugar.
If using the added fat method, be sure to stir the oil and lecithin well to emulsify them.
Put into an airtight jar while still warm. If you let it sit and cool, a film will form at the top of your creamer.