01 - Preheat oven to 425°F. Line a standard baking sheet with parchment paper.
02 - Remove all leaves from cauliflower and trim the stems without detaching the core to ensure stability.
03 - Position cauliflower stem-side down on a cutting board. Cut each head into 2 to 3 thick steaks, approximately 3/4 inch thick. Reserve any extra florets for roasting.
04 - In a small mixing bowl, thoroughly whisk the olive oil, smoked paprika, garlic powder, cumin, black pepper, salt, and lemon juice until well combined.
05 - Evenly arrange steaks and reserved florets on the prepared baking sheet. Generously brush both sides with the marinade, ensuring full coverage.
06 - Roast in the center of the oven for 15 minutes. Using a large spatula, flip steaks gently and continue roasting for an additional 12 to 15 minutes until golden brown and fork-tender.
07 - Transfer cauliflower steaks to serving plates. Sprinkle with chopped fresh parsley and serve alongside lemon wedges.