Preheat oven to 400F.
Slice tomatoes, onions, and smashed garlic, then layer evenly across a roasting pan lined with a bed of fresh herbs and flowering chives. Drizzle with olive oil, dust with 2 pinches of sugar and dried cayenne pepper, top with a large handful of pine nuts, and season liberally with sea salt and black peppercorns.
Roast in the oven, uncovered, until tomatoes begin to char and onions caramelize, approximately 30 minutes. Remove from oven and rest for 5 minutes. Separate rosemary and thyme leaves from their sprigs, discarding the sprigs. Spoon contents of the pan, including juices, oils, seasonings and carbonized bits into a blender (or food processor). Add Parmesan cheese, chicken stock, milk and a quarter-cup of cream. Toss back in rosemary and thyme leaves. Pulse, then blend on high for one minute, or until desired consistency achieved.
To plate, spoon soup into a bowl, garnish with a dollop of creme fraishe, toasted pine nuts, fresh herbs, and roasted sourdough croutons. Season additionally, to taste, and serve.