Put the seeds in a small frying pan and dry toast on low heat for few minutes, until lightly brown. Transfer to a spice grinder or pestle and mortar, and grind to a powder. Heat the oil in a saucepan on medium heat and fry the onion, garlic, and ginger until soft. Add carrots, squash, boullion powder, spices, lemon juice, and water and bring to boil. Turn down the heat to medium-low and leave to simmer for 25 minutes, until the vegetables are tender. Then add the coconut milk and blend it smooth with a hand blender or a food processor.