Roasted Butternut Squash Soup with Roasted Butternut Squash Seeds

large butternut squash (peeled and cut into 1-inch cubes, save the seeds for the garnish)

carrots (coarsely chopped)

large onion (coarsely chopped)

garlic (peeled)

sprigs of thyme

olive oil (plus additional for roasting seeds)

cayenne pepper

salt and pepper

vegetable broth