Heat oil in large soup pot.
Add onions and saute for about 5-6 minutes.
Add garlic and ginger and cook for an additional 2 minutes.
Stir in curry paste, sugar, and salt for an additional minute.
Add squash, broth, and coconut milk and bring to a boil.
Reduce heat and simmer for 20-25 minutes or until squash is tender.
Use an immersion blender to puree soup if desired (I like to leave some chunks).
Stir in shrimp and simmer for 2-3 minutes until pink and cooked through.
Top with thai basil or cilantro and jasmine rice if desired