Zuppa di Pesce (Fish Soup)

Ingredients:

• ½ cup olive oil

• 1 onion, slivered

• 4 tender inner stalks celery, cut thin on bias

• Celery leaves from stalks

• ½ bulb fennel, trimmed, cored, and thinly sliced

• 1 pound shrimp

• 2 cups white wine

• 1 14-ounce can diced tomatoes

• 2 quarts water

• 1 pound cod, cut in 2-inch pieces

• 12 clams

• 2 pounds mussels

• ¼ cup fresh parsley

• ¼ cup fresh oregano or 1 tablespoon dried oregano

• Salt

• Pe…