Prepare the Cauliflower: Heat your oven to 375°F with a rack positioned in the center. Line a large baking sheet with foil and spray with non-stick spray. Wash and cut the cauliflower into large chunks. Toss with 1 tablespoon of olive oil, then spread evenly on the prepared baking sheet. Bake for about 20 minutes, or until barely tender. Take care not to overcook.
Cool and Process: Let the roasted cauliflower cool for about 20 minutes. Transfer it to a food processor and pulse until it reaches a rice-like texture. Work in batches if needed, and avoid over-processing to prevent it from becoming mushy.
Assemble the Salad: In a large bowl, combine the processed cauliflower, radishes, scallions, red onion, garlic, parsley, mint (if using), cucumber, and tomatoes.
Dress the Salad: Drizzle with the remaining 3 tablespoons of olive oil, lemon juice, lemon zest, salt, and pepper. Toss everything together until well combined.
Chill and Serve: Cover the bowl with plastic wrap or transfer the salad to an airtight container. Refrigerate for at least 1 hour to allow the flavors to meld. This salad can be stored in the fridge for up to 5 days.