Preheat oven to 425 degrees
On a large rimmed baking pan, toss together broccoli, olive oil, garlic, salt & pepper. Spread evenly.
Bake for about 15 minutes, until edges start to brown. Flip and bake an additional 5 to 10 minutes to desired tenderness.
Drizzle with lemon juice. Sprinkle with red pepper flakes if desired. Toss and serve.