Scoop flesh out of butternut squash with a spoon. In a medium saucepan, combine broth, flesh of butternut squash, garlic powder, onion powder, curry powder, salt and pepper. Set pot over medium heat and bring to a simmer, about 10 minutes. Puree soup with an immersion blender until smooth. Ladle into bowls. Serve with a dollop of Lime Crema and garnish with extra lime zest, if desired.
In a small bowl, combine sour cream, lime zest, and lime juice. Whisk to combine.