Heat the oil in a large soup pot over medium-high heat. Add the onion and saute for 3 to 4 minutes before adding the garlic, ginger, curry paste and hot sauce. Saute for another couple minutes.
Add the sweet potatoes and carrots, seasoning well with salt and pepper. Mix together well so the vegetables are well-coated and then pour in the broth.
Bring the mixture to a boil, before reducing to low. Simmer for 25 minutes or until the veggies are tender.
Remove from the heat, and carefully use an immersion/stick blender to puree the soup. You also can use a high-speed blender to puree the soup in batches, being careful to avoid backsplash.
Return to the pot and stir in the coconut milk, and add salt and pepper to taste.
Serve the soup topped with an optional lime wedge and sprinkling of pumpkin seeds. This also tastes great with a little goat cheese stirred in.