Preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper for easy cleanup.
In a large bowl, combine the cauliflower florets, minced garlic, olive oil, onion powder, garlic powder, red pepper flakes, salt, and pepper. Toss until the cauliflower is evenly coated.
Spread the cauliflower mixture in a single layer on the prepared baking sheet.
Roast the cauliflower in the preheated oven for 20 minutes. Remove from the oven and sprinkle the grated Parmesan cheese evenly over the top.
Return the baking sheet to the oven and roast for an additional 10-15 minutes or until the cheese is melted and golden brown, and the cauliflower is tender and slightly crisped on the edges.
Remove from the oven, and let it cool for a few minutes. Garnish with chopped fresh parsley before serving.