Preheat your oven to 200°C (400°F) and line a baking sheet with parchment paper for easy cleanup.
Trim the broccoli into uniform bite-sized florets, keeping the stems intact if you like them softer, and spread them out on the prepared baking sheet.
Peel the garlic cloves and either crush them using the side of a knife or slice thin, then scatter evenly over the broccoli.
Drizzle the olive oil over the broccoli and garlic, then sprinkle generously with salt and a few cracks of black pepper. Toss everything gently to coat evenly.
Arrange the broccoli in a single layer on the baking sheet, making sure the garlic is evenly distributed for even caramelization.
Place the baking sheet in the oven and roast for 20-25 minutes, flipping halfway through, until the edges are golden brown and fragrant, and the garlic is caramelized but not burnt.
While the broccoli roasts, cut the lemon in half and squeeze out fresh juice, set aside for drizzling later.
Once done, remove the broccoli from the oven and transfer to a serving dish. Squeeze the fresh lemon juice over the warm florets for a bright, tangy finish.
Gently toss to coat the broccoli in the lemon juice, then taste and adjust seasoning with more salt or pepper if needed.
Serve immediately while warm, enjoying the crispy edges and fragrant, caramelized garlic.