In a large mixing bowl, combine the broccoli florets and minced garlic.
Drizzle the olive oil over the broccoli and garlic, then sprinkle lemon zest, lemon juice, red pepper flakes (if using), salt, and pepper. Toss everything together until the broccoli is well coated.
Spread the broccoli mixture in a single layer on a baking sheet lined with parchment paper.
Roast in the preheated oven for about 20-25 minutes, or until the broccoli is tender and slightly crispy on the edges, stirring halfway through for even roasting.
If desired, sprinkle the grated Parmesan cheese over the broccoli during the last 5 minutes of roasting.
Once finished, remove from the oven and garnish with fresh parsley before serving.
Notes
Optional Parmesan cheese can be added for extra flavor.