Pat the piece of fish dry with paper towels and salt and pepper each side .

Heat olive oil in the saucier over medium heat.

Sauté sliced onions and fennel until they soften, about 5-10 minutes.

Add chopped garlic and sauté until aromatic, about 1-2 minutes.

Add tomato paste and thyme, stirring until the paste is well blended and begins to darken.

Add lemon zest, tomatoes, and olives. Cook until tomatoes begin to soften.

Add fresh parsley and combine.

Add white wine and simmer until volume is reduced by half.

Add the fish to the pan and add stock until the fish is mostly covered.

Add the bay leaf to the pan.

Bring the broth to a boil and reduce it to a simmer for 10 minutes.

Turn the fish and simmer for an additional 10 minutes or until the fish is tender and flaky.

Break up the fish and stir well.

Serve with crunchy bread or crostini.