Cut a small sheet of aluminum foil. Lightly drizzle with olive oil over the garlic bulb. Seal the foil and place on the baking sheet with the butternut squash and/or apples. Roasting time is 20-25 minutes. Set aside and allow to cool. Once the garlic is cool enough to safely handle, the soft pulp will gently squeeze out. Set aside. You will have leftover roasted garlic to use in other ways-- terrific in mashed potatoes. On a parchment or foiled lined baking sheet, dump the diced butternut squash. Drizzle a little olive oil (1-2 Tbsp.) and sprinkle with some coarse salt & black pepper. With your hands, toss the squash to coat and season evenly. Roast for approximately 20 minutes, until tender and lightly golden on the edges.
On a separate baking sheet, do the same for the apple chunks. (You could roast it all one one large pan, if you have room.) Roast for about 15 minutes.
In a Dutch Oven, add a bit of olive oil (enough to lightly coat the pan) and one small pat of unsalted butter, on medium heat.
Add the leeks and cook until tender, about 2-3 minutes.
Add the curry (if you are using it) and stir for about 15 seconds.
Add 2-3 cloves of the roasted garlic. (Note you can add fresh garlic, but use 1 small clove and be careful it doesn't burn.)
Add the roasted squash, diced potato, apples, the white wine and apple juice.
Add 2-3 cups of chicken stock-- enough to just cover the vegetables and fruit.
Tie the thyme & bay leaves with kitchen twine. (NOTE: You can add the thyme directly to the soup, but I used a bouquet garni just to flavor the broth. I wanted to remove the herbs for aesthetic purposes only.)
Bring to a boil, then reduce to a simmer on low heat. Allow the soup to cook for 20-30 minutes. NOTE: If you opted not to roast the vegetables, allow to simmer about 45 minutes, so that the vegetables and apples can cook to fork tender.
Using an immersion blender, puree the soup until smooth. Otherwise, use a blender to puree in batches. Be very careful to put a towel over the top of the blender.
The soup will be quite thick (from the potato starch).
Taste and adjust your seasonings with more salt, if necessary.
If desired, add heavy cream or whole milk to thin and give a lighter color and richer flavor. Otherwise, add more chicken or vegetable stock, until it reaches your desired consistency.