Skim the creamy top off the coconut milk and put into a large saucepan with the curry paste over medium heat.
Let it sizzle while using a fork to beat together until combined. Continue beating gently while adding the rest of the coconut milk, fish stock, fish sauce, sweetener, lemongrass, lime leaves and turmeric.
Bring to a boil and add the butternut squash. Cook on a fast simmer until the squash is tender, about 15 minutes.
Add the shrimp and cook about 4 minutes until fully cooked.
Stir in green vegetables. Once wilted, add lime juice.
Pour into a large serving bowl and sprinkle with cilantro just before serving.