Preheat your oven to 220°C (430°F) and line a baking sheet with parchment paper.
Trim the leaves and core from the cauliflower, then rinse and pat dry thoroughly.
Place the cauliflower upright on a cutting board and slice into 1.5-inch thick steaks, aiming for 2-3 slices from the head. Save any leftover florets for other dishes.
In a large bowl, whisk together olive oil, minced garlic, paprika, salt, and pepper until combined.
Use a silicone brush to coat both sides of each cauliflower steak generously with the spice mixture, making sure the edges are well covered.
Arrange the coated steaks on the prepared baking sheet, spacing them apart for even roasting.
Roast in the oven for 20 minutes, then carefully flip each steak with a spatula and roast for an additional 15-20 minutes, until edges are golden and caramelized, and the interior is tender.
Once done, squeeze fresh lemon juice over the steaks for brightness, and sprinkle with chopped herbs if using.
Let the steaks rest for a few minutes, then serve hot, showcasing their crispy edges and tender, smoky interior.