Caramelizing cauliflower takes it to a whole new level. Olives and clementines lend salty, citrusy swagger.
Preheat oven to 450 degrees. Arrange cauliflower in a single layer on a rimmed baking sheet and brush both sides with 2 tablespoons oil. season with salt and pepper. Roast, flipping one, until tender and golden, about 25 minutes. Transfer to a serving platter with clementine segments and olives.
Meanwhile, make vinaigrette: Whisk remaining oil with vinegar and clementine zest and season with salt. Drizzle over cauliflower, clementines, and olives and sprinkle with parsley.