Cioppino is a fish stew, a descendant of the various regional fish soups and stews of Italian cooking. It was developed by the fishermen who settled in the North Beach section of San Francisco. Originally it was made on the boats while out at sea and later became a staple as Italian restaurants proliferated in the city. The name comes from the Italian ciuppin, a word which described the local fish stew in the regional dialect of the port city of Genoa.
The below recipe is based on one by Giada De Laurentiis.
Cleaning and eating mussels 
This recipe calls for live mussels. Here are some safety guidelines for buying, eating and cooking live bivalves (mussels and clams):
- Never buy a mussel/clam that's open or cracked.
- Never eat a mussel/clam that won't open after cooking.
- Cook mussels/clams within 24 hours of purchasing.
- Always brush mussels/clams clean before cooking. Remove beards from mussels as well.
For more on this subject have a look at Happy as a clam by Chef Mark R. Vogel
- 3 tablespoons olive oil
- 1 large fennel bulb, thinly sliced
- 6 ounces onion, chopped
- 8 ounces of celery, chopped
- 3 large shallots, chopped
- 2 teaspoons salt
- 4 large garlic cloves, finely chopped
- 3/4 teaspoon dried crushed red pepper flakes, plus more to taste
- 6 ounces tomato paste
- 2 pounds diced tomatoes
- 1 1/2 cups dry white wine
- 5 cups of water
- 1 bay leaf
- 2 pounds crabs, any type, cut into pieces
- 2 pounds mussels, scrubbed, debearded
- 1 pound scallops
- 1 1/2 pounds tilapia cut into two-inch chunks (or substitute any fish with a white, firm flesh)
- 2 loaves of San Francisco sourdough bread or any other bread with a chewy crust
- Heat the oil in a very large pot over medium heat.
- Add the fennel, onion, shallots, and salt and sauté until the onion is translucent.
- Add the garlic and three quarters of a teaspoon of red pepper flakes, and sauté for two minutes.
- Stir in the tomato paste.
- Add tomatoes with their juices, wine, water, crabs, celery and bay leaf. Cover and bring to a simmer. Reduce the heat to medium-low. Cover and simmer for about 30 minutes to allow the flavors to blend.
- Add the mussels to the cooking liquid. Cover and cook until the mussels begin to open. This should take about five minutes.
- Add the scallops and fish. Simmer gently until the fish and scallops are just cooked through and all the mussels are completely open, gently stirring occasionally. This should take about another 10 minutes.
- Check the soup for closed mussels and throw them out. Remove the bay leaf.
- Season the soup, to taste, with more salt and red pepper flakes.
- It's customary to serve cioppino with San Francisco sourdough bread. However, any bread with a thick, chewy crust will do.