01 - Preheat oven to 425°F. Line a large baking sheet with parchment paper.
02 - Remove leaves from cauliflower and trim stem while keeping core intact. Slice each head into 1-inch-thick steaks, yielding approximately 2-3 steaks per head.
03 - Arrange steaks on prepared baking sheet. Brush both sides generously with olive oil.
04 - In a small bowl, combine cumin, smoked paprika, garlic powder, salt, and pepper. Sprinkle evenly over both sides of steaks.
05 - Roast for 25-30 minutes, flipping steaks halfway through, until golden brown and tender when pierced with a fork.
06 - While cauliflower roasts, whisk together tahini, lemon juice, water, minced garlic, maple syrup, and salt in a bowl. Add water gradually until dressing reaches creamy, pourable consistency.
07 - Arrange roasted cauliflower steaks on serving platter. Drizzle generously with tahini dressing. Top with parsley, toasted nuts if desired, and lemon wedges.