In a large pot combine squash, garlic, stock and butter over medium-high heat and bring to a boil. Reduce and simmer for 30 minutes or until squash is tender.
Stir in evaporated milk and curry paste to taste. Use a food processor or an immersion blender and puree until smooth.
Add shrimp and lightly simmer for another 15-20 minutes. Salt to taste.
Notes
*Coconut milk can curdle if heated at too high of temperature (compared to evaporated milk which will not curdle)