Preheat a standard oven to 375°F or a convection oven to 350°F.
Combine tomato, onion, oil, basil, first amount of salt, first amount of pepper, and garlic. Mix well and set aside.
Combine breadcrumbs, butter, and Parmesan. Toss to mix.
On sheet pan coated with cooking spray, place fish fillets 1" apart. Season with second amount of salt and second amount of pepper.
Top each fillet with ¼ cup of the crumb mixture.
Bake until internal temperature of fish reaches 145°F and crumb mixture is golden brown, about 10 to 15 minutes.
To serve, plate one piece of pollock with 2 tablespoons of the bruschetta mixture.