In a large dutch oven, over medium heat, cook bacon until crisp. Remove bacon from pan. Add onion and garlic to bacon fat, cook 4 - 5 minutes or until the onion is transparent. Add scallions and red pepper flakes. Add wine and bring to a boil. Boil 1 minute, add mussels, cover and cook 5 - 6 minutes or until the mussels have opened. Top with reserved bacon pieces. Serve with baguette slices.