1) Add butter, olive oil, garlic and onions to a large pot. Sauté until onions are translucent.
2) Add red pepper flakes, bay leaf, salt and pepper, and continue to sauté.
3) Add white wine and bring to a boil.
4) Add mussels, cover and reduce heat. Cook until mussels open, about 5-6 minutes. Discard mussels that do not open.
5) Remove from heat and serve with warm sliced Italian bread. Great for dipping!
6) Serve with Pinot Grigio, Sauvignon Blanc or other crisp light white wine.