01 - Preheat oven to 425°F. Line a baking sheet with parchment paper for easy cleanup.
02 - Spread cauliflower florets on the prepared baking sheet. Drizzle with olive oil and season lightly with salt and black pepper. Roast for 20–25 minutes until golden and tender, stirring halfway through cooking. Allow to cool before assembling.
03 - In a large bowl, whisk together mayonnaise, sour cream, lemon juice, Dijon mustard, garlic powder, smoked paprika, salt, and pepper until completely smooth and well combined.
04 - Add roasted cauliflower, cherry tomatoes, romaine lettuce, green onions, crumbled bacon, and cheddar cheese (if using) to the bowl with the dressing. Gently toss to coat all ingredients evenly.
05 - Taste the salad and adjust seasoning with additional salt and pepper as needed. Serve immediately or refrigerate for up to 2 hours to allow flavors to meld together.