Place mussels in pan of fresh water so they will expel out any sand & grit while you make the cooking broth. (leave for 15-20 minutes).
Melt butter in heavy pan (I use an enameled cast iron one). Saute garlic until translucent.
Add wine and saffron, simmer for a couple of minutes on medium heat.
Add clamato juice, curry powders, green onions, tomatoes.
Continue simmering on low, and add a bit of sea salt and additional curry powder if you like to taste (if you like it with more heat, you can also add a little freshly chopped chili pepper).
While broth gently simmers, remove mussels one at a time from soak, scrub with a soft brush, and rinse with fresh water, (don't just dump into a collander as the grit they expel will follow -- ).
When mussels are cleaned, add to broth and simmer for 4 to 5 minutes (until shells are fully opened). Discard any mussels that do not open. Place in serving bowls and ladle broth over. Serve with hot fresh baguette or other rustic bread.