Mix all ingredients together. Add 2 cups of cold water to the magic mixture and cook the mixture in a large saucepan, stirring constantly, until thickened. Add the main ingredients (mushrooms or celery, broccoli or asparagus) and heat a few minutes longer. Soup can be pureed in blender if your don’t want chunks of veggies. The powdered soup mix will keep in an airtight container for sometime.