Preheat oven to 425° and bring a large pot of water to a boil.

Once the water is boiling, add the broccoli and cook for 3 minutes. Remove and rinse under cold water and drain. Place back into pot.

Meanwhile heat the oil and garlic in a small saucepan over low to medium-low heat. Make sure the heat is low enough that the garlic is not cooking too fast. After the oil and garlic has heated for 5 to 8 minutes; the garlic should be turning golden brown, but not burning, then add the crushed chili pepper flakes and heat for an additional minute then turn off the burner and strain chili-garlic oil into a small heat-proof bowl.

Squeeze the juice of half a lemon over top of the par-cooked broccoli and then drizzle with the chili and garlic infused oil. Toss everything together well so that each piece of broccoli has a thin coating of oil. Using tongs, so that the excess oil drains off, remove the broccoli to a rimmed baking sheet and spread it out in a single layer. Sprinkle with kosher salt and black pepper.

Place broccoli in a preheated oven for about 15 minutes. If your oven tends to be hot, check the broccoli earlier. If you like it to be extra tender, leave it in longer.

After the broccoli has roasted for 15 minutes, remove and grate some fresh Parmesan cheese over top and place back in the oven for 2-3 more minutes.