Pre-heat oven to 400 F (200 C). Line rimmed baking sheet with unbleached parchment paper. Place squash, cauliflower, and onion items on lined baking sheet. Drizzle with olive oil and ensure all greens are coated and distributed evenly. Use one other lined baking sheet if required. Place in oven and bake for 25 minutes.
In the meantime, in massive pot, heat broth or water on medium-low warmth, whereas greens are in oven.
After greens are carried out roasting, take out of oven. Fastidiously add to soup pot. Add salt and blend properly.
You need to use an immersion blender or a vented blender. Place immersion blender into soup pot and thoroughly purée soup till clean. If utilizing vented blender, rigorously add soup into blender container and purée till clean. This will should be carried out in a number of batches.
Serve heat with some freshly floor black pepper. High with some pumpkin seeds, if desired. Take pleasure in!