1 pound broccoli, trimmed and cut into florets
3 tablespoons vegetable oil
Coarse salt and ground pepper
1 Portuguese roll, torn into large pieces
2 teaspoons chopped fresh thyme
2 tablespoons butter, melted and cooled
4 fillets skinless, boneless, firm, white-fleshed fish such as haddock, cod, or halibut (1 1/4 pounds total and each 1/2 inch thick)
Lemon wedges, for serving

Preheat oven to 425 degrees, with rack in upper third. On a rimmed baking sheet, toss broccoli, 2 tablespoons oil, 1 teaspoon salt, and 1/4 teaspoon pepper. Roast until broccoli is tender and lightly browned, 15 to 20 minutes, tossing halfway through. Meanwhile, in a food processor, pulse bread, thyme, 1/4 teaspoon salt, and 1/8 teaspoon pepper until coarse crumbs form. Transfer breadcrumbs to a bowl and stir in butter with a fork. Coat another rimmed baking sheet with 1 tablespoon oil. Arrange fish on sheet and season with salt and pepper. Top each fillet with enough breadcrumbs to coat, pressing firmly to adhere. Bake until fish is opaque throughout and breadcrumbs are golden brown, about 8 minutes. Serve fish with broccoli and lemon wedges.