1. Remove any discolored outer leaves from brussels sprouts and cut off stem ends. Slash bottom of each sprout with a shallow X.
2. Heat 1 inch of water in a steamer and bring to a boil. Place brussels sprouts in a colander or steamer basket, cover, and steam for 10 minutes or until tender.
3. Combine yogurt, Dijon mustard, caraway seeds, and black pepper.
4. Toss yogurt sauce with brussels sprouts.