01 - Preheat the oven to 425°F. Line a baking sheet with parchment paper.
02 - Remove the leaves and trim the stem of each cauliflower head, leaving the core intact.
03 - Place cauliflower heads stem-side down and slice into ¾-inch thick steaks, yielding 2 to 3 steaks per head. Reserve any loose florets for another use.
04 - Combine olive oil, smoked paprika, garlic powder, ground cumin, black pepper, and sea salt in a small bowl, mixing thoroughly.
05 - Arrange steaks on the prepared baking sheet and brush both sides generously with the spiced oil mixture.
06 - Roast steaks in the oven for 15 minutes, then carefully flip and roast for an additional 12 to 15 minutes until golden brown and tender.
07 - Transfer to serving plates, sprinkle with chopped parsley, and provide lemon wedges alongside.