Mince the garlic and shallots, and set aside.
Leaving the skin on, cut the kabocha into quarters. Preheat the oven to 375 degrees F.
In a bowl, combine oil, salt, and herbs de Provence. Rub the flesh of each kabocha with the mixture. Roast on a baking tray for 45 minutes, or until the flesh is soft and can be scooped with a spoon. Blend the squash until smooth. Reserve 3 cups of the puree for the soup.
Have more stock handy than the recipe calls for depending on how thick you want the soup.