Preheat oven to 400°F (200°C).
Place the butternut squash halves cut-side up on a baking sheet. Drizzle with 1-2 tbsp of olive oil and season with salt and pepper.
Roast the squash for 45-60 minutes, until very soft.
In a large pot, heat the remaining 2-3 tbsp of olive oil over medium heat. Add the sliced onions and sauté for 10-15 minutes, until translucent and caramelized.
Add the peeled garlic cloves and carrot to the pot. Sauté for 5 more minutes.
Scoop the roasted butternut squash flesh into the pot. Add the paprika, turmeric, garlic salt, and cayenne (if using). Season with salt and pepper to taste.
Pour in the chicken bone broth and bring the mixture to a simmer. Cook for 10-15 minutes, until the vegetables are very soft.
Using an immersion blender (or regular blender), purée the soup until smooth and velvety.
Stir in the heavy cream and adjust seasoning if needed.
Serve the soup hot, topped with croutons, shredded Gruyère cheese, and pumpkin seeds.
