Preheat the oven to 425°F (220°C) and allow it to heat for at least 5 minutes.

Rinse 1.5 pounds of broccoli crowns under cool running water and pat completely dry with paper towels.

Cut the broccoli into even 2 to 3-inch florets to ensure uniform roasting.

In a small bowl, combine 1 teaspoon garlic powder, 1 teaspoon onion powder, 0.5 teaspoon smoked paprika, 0.5 teaspoon sea salt, 0.25 teaspoon black pepper, and 0.25 teaspoon red pepper flakes.

In a large bowl, toss the broccoli florets with 3 tablespoons olive oil until evenly coated, then sprinkle the spice mixture over the florets and toss again.

Arrange the seasoned broccoli in a single layer on a sheet pan lined with parchment paper or aluminum foil, placing florets cut-side down when possible.

Roast in the preheated oven for 18 to 22 minutes, shaking the pan gently at the 10-minute mark, until the edges are deeply browned and the centers are tender.

Remove from the oven, transfer to a serving platter, and top with Parmesan cheese and a squeeze of fresh lemon juice if desired.