In a small bowl or glass, add 1/4 tsp saffron to 1/2 cup white wine and set aside
Heat oil in a large pot over med-high and then add chopped fennel, celery, onions. Saute mixture until translucent (about 5 minutes). Add chopped garlic for 30 seconds to a minute.
Add next 8 ingredients (tomato paste through salt) to the pot and bring to a low boil. Turn down heat and simmer broth for about 30 minutes. If you want more liquid in the soup, add another cup of water, clam juice or wine at this point.
Taste the broth for salt and flavor. If desired, add the cayenne and/or more salt or Pernod.
Add the white fish to the pot and cook for 3-5 minutes, until no longer transcluent. Be careful not to overcook. Add shrimp and mussels to the pot and cook for an additional 2-3 minutes.
Taste again for seasoning and adjust to your taste. Serve with low carb almond flour crackers if low carb. Otherwise, serve with crusty French bread.