01 - Preheat oven to 425°F. Line a large baking sheet with parchment paper.
02 - Toss cauliflower florets with olive oil, salt, and pepper until evenly coated. Spread in a single layer on prepared baking sheet.
03 - Roast for 25 to 30 minutes, flipping halfway through, until cauliflower is golden brown and tender with crispy edges.
04 - While cauliflower roasts, whisk together mayonnaise, sour cream, chili powder, smoked paprika, garlic powder, and lime juice in a large bowl until smooth.
05 - Transfer hot cauliflower to bowl with sauce. Toss thoroughly until every piece is evenly coated.
06 - Add half the cotija cheese, half the cilantro, red onion, and jalapeño if using. Toss gently to distribute.
07 - Transfer to serving platter. Sprinkle with remaining cotija cheese, extra chili powder, and remaining cilantro. Serve warm with lime wedges.