Preheat grill pan or outdoor grill to medium-high to high heat.
Coat the fish in extra-virgin olive oil and season with salt and pepper. Cook fish for about 3 to 4 minutes on each side until firm, cooked through and evenly marked. Char bread on the grill 1 minute on each side.
While fish cooks, in the bottom of a medium bowl, combine anchovy paste, grated garlic, red pepper flakes, zest and lemon juice and whisk in 1/4 cup extra-virgin olive oil. Add capers, olives, parsley and tomatoes. Toss and season with black pepper, to taste.
Serve bread topped with lots of salsa and fish.