Whisk together rice milk and cornstarch in a small saucepan until well combined.

Add vegan margarine, chicken bouillon granule (if using for soup), salt, and pepper to the saucepan.

Stir the mixture constantly over medium heat until it comes to a boil.

Reduce the heat to low and simmer for 1-2 minutes, stirring continuously, until the sauce thickens to your desired consistency.

For cream of chicken soup, add canned chicken during the last minute of simmering.

For cream of mushroom soup, add a can of mushrooms during the last minute of simmering.

Use as a white sauce over vegetables, pasta, or other dishes.