Place a large skillet in the oven and preheat to 325°F.
When hot add the olive oil to the pan. Swirl to coat.
Add the carrots, onions, and ginger, and toss well.
Place the pan in the oven on the center rack and roast for 90 minutes, stirring occasionally.
While the carrots are roasting, place the bell pepper on a piece of aluminum foil on the top rack.
Allow the pepper to blacken on all sides, turning frequently, about 15-20 minutes.
Once the pepper is blackened, remove it from the oven and place it, whole, in a small paper bag. Fold the top closed and set the bag aside to allow the pepper to cool.
When the pepper is cooled, the blackened skin should slip off easily. Discard the skin, stem, and seeds and chop the pepper coarsely. Set aside.
After 90 minutes, remove the pan from the oven and place the carrot mixture in a large saucepan with tall sides.
Add the stock, water, milk, and salt, stir thoroughly, then with a stick blender, puree the soup smooth. Before serving, bring the soup to temperature over low heat, stirring frequently.
Serve topped with one-fourth of the roasted bell pepper.
