This is the perfect way to show off the stunning red-orange color of these Kyoto carrots. Their wonderful sweetness and flavor means that you don’t need stock to make this soup, but if you have some nice stock you can certainly use it. Preheat your oven to 400 degrees. Wash the carrots and cut them into ½” rounds. Toss with the olive oil. Season with salt and pepper. Spread out in a single layer on a baking sheet and roast in the oven until tender, about 20 minutes. Give them a stir about half way through to ensure even cooking. Put the carrots in your blender with two cups of water and puree until completely smooth: you’ll want to leave the blender running for a few minutes. Put the soup in a small pot over low heat. Add enough water to thin the soup to a smooth puree. Check the seasoning. Serve the soup garnished with a dollop of yogurt, a few pieces of blood orange and a squeeze of lemon.