Adjust the oven rack to the lowest position and heat the oven to 450°F. Toss the broccoli with olive oil, salt, and pepper on a rimmed baking sheet until evenly coated. Spread the broccoli into a single layer, ensuring the cut sides are touching the pan for maximum browning.

Roast the broccoli until the florets are browned and tender, about 20 minutes, rotating the pan halfway through.

Combine the olive oil, garlic, and red pepper flakes in an 8-inch skillet over medium-low heat. Cook, stirring often, until the garlic softens and just begins to turn golden around the edges, about 5 to 7 minutes.

Remove the skillet from the heat and stir in the olives, oregano, and lemon juice. The residual heat will wake up the herbs without scorching them.

Transfer the roasted broccoli to a large bowl and toss with the olive oil mixture. Serve hot, while the florets are still crisp.