Set the racks in the upper and lower thirds of the oven and preheat it to 425°F.
Line two large rimmed baking sheets with parchment paper.
Divide the broccoli between the sheets, arranging them in a single layer. Drizzle each sheet of broccoli with ¼ cup oil, then season each with ½ teaspoon salt and a few grinds of pepper.
Roast, stirring once and rotating the sheets halfway through, until the broccoli is crispy and charred in spots, 35 to 40 minutes.