1. In a medium Dutch oven or saucepan, combine oil and garlic; cook over medium-high until garlic is fragrant, 1 minute. Add fennel and cook, stirring frequently, until slightly softened, about 3 minutes. Add tomato, season with salt and pepper, and cook, stirring frequently, until tomato is breaking down, about 3 minutes.
2. Stir in broth and bring stew to a gentle boil. Reduce to a simmer.
3. Gently fold in seafood. Return to a bare simmer and cook until seafood is opaque throughout, about 3 minutes. Serve stew topped with fennel fronds and a drizzle of oil, with bread alongside.