01 - Preheat your oven to 425°F. Line a large baking sheet with parchment paper.
02 - Remove the leaves and trim the stem end of each cauliflower head, keeping the core intact to maintain the steak structure.
03 - Place each cauliflower head upright on a cutting board and slice crosswise into 1-inch thick steaks. You should get 2–3 steaks per head. Reserve any loose florets for another use.
04 - In a small bowl, whisk together the olive oil, smoked paprika, cumin, garlic powder, black pepper, salt, chili powder, and lemon juice until well combined.
05 - Arrange cauliflower steaks on the prepared baking sheet. Brush both sides generously with the marinade, ensuring even coverage.
06 - Roast for 20 minutes, flip carefully with a spatula, and roast another 10 minutes until golden brown and tender when pierced with a fork.
07 - Transfer to serving plates. Sprinkle with fresh parsley and serve with lemon wedges, if desired.