Heat the olive oil in a large pot then add the onion and garlic. Cook this over mediumheet for about five minutes or until the onion is soft.
Add the mustard seed, tumeric, ginger, cumin, cinnamon, cayenne pepper and salt. Cook this for about 2 minuts on a medium heat. Stir carefully and constantly.
Whisk in each of the following, water or vegetable stock, pumpkin, maple syrup, and lemon juice. Simmer this mixture for 15 minutes. Continue stirring.
The last step - Stir in the soy milk, then puree the soup in a blender until very smooth. Depending on the size of your blender you may have to do this in two or more batches. When blended, return the soup to the pan and heat on medium until hot and steamy without boiling, ten minutes or less.
Serve with a sprinkling of fresh cilantro. This is also pleasant from steaming mugs.