Preheat your oven to 220°C (425°F) and line a baking sheet with parchment paper. Prepare your cauliflower by cutting it into bite-sized florets, keeping the pieces uniform for even roasting.
In a large mixing bowl, toss the cauliflower florets with the olive oil, ensuring each piece is well coated. Sprinkle with salt and pepper, then toss again to distribute evenly.
Spread the cauliflower evenly on the prepared baking sheet, making sure the pieces are not crowded. Place in the oven and roast for 20 minutes, flipping halfway through, until the edges are golden brown and fragrant.
While the cauliflower roasts, combine the paprika with a pinch more salt if desired in a small bowl. Prepare for seasoning after roasting.
After 20 minutes, remove the cauliflower from the oven and sprinkle the paprika mixture over the hot florets. Toss gently with a spatula to coat evenly, then return to the oven for an additional 10 minutes, or until crispy and deeply golden.
Once done, remove from the oven and transfer to a serving plate. Drizzle with fresh lemon juice for a bright, zesty finish, then toss lightly to combine.
Let the cauliflower bites rest for a couple of minutes to set the crispiness. Serve immediately while warm, enjoying the crunchy exterior and tender interior.