Preheat oven to 425 degrees F.
To a large rimmed baking sheet, add the cauliflower florets.
Drizzle the olive oil over them and toss to coat the cauliflower in oil.
Sprinkle the paprika, salt and pepper onto the cauliflower and toss again to coat.
Spread the cauliflower into a single layer on the baking sheet and bake for 20-25 minutes, until golden and tender.
Remove from the oven briefly to sprinkle the garlic over the cauliflower (and parmesan, if using).
Return to the oven and bake for 5 more minutes.
Remove from the oven and drizzle fresh lemon juice on top of the roasted cauliflower.
Garnish with fresh parsley and serve immediately.