Heat oil in a Dutch oven over medium-high heat. Add leek, onion, and carrots; sauté 7 minutes or until tender. Pierce habanero several times with a knife. Add habanero, ginger, and garlic to pan; sauté 2 minutes. Stir in wine, scraping pan to loosen browned bits. Add water and sweet potato; bring to a boil. Partially cover, reduce heat, and simmer 30 minutes or until tender. Stir in orange juice and coriander. Remove and discard habanero.
Place half of carrot mixture in a blender; process until smooth. Pour pureed mixture into a medium bowl; repeat procedure with remaining carrot mixture. Press carrot mixture, in batches, through a large fine sieve into pan; discard solids. Stir honey and salt into carrot mixture; cook over medium heat 5 minutes or until thoroughly heated. Ladle into bowls; top with low-fat yogurt. Garnish with cilantro leaves, if desired.