PREPARE CAULIFLOWER: Cut cauliflower in half. Rinse well and pat dry with paper towels. Remove green leaves and the bottom part of the core/stem. Cutting from the core side, cut each half into 4 wedges. Lay wedges on a pan lined with foil and sprayed with oil. Mix olive and sesame in a small cup and brush wedges on all sides. Sprinkle with salt and pepper.
ROAST: Roast cauliflower for 10 minutes on one one side, gently flip over with tongs or spatula, then roast for another 10 minutes on other side.
MAKE DRIZZLE: While cauliflower is roasting, add all orange-balsamic drizzle ingredients to a small saucepan. Heat to medium high and cook for about 3 minutes or until reduced and slightly thickened (enough to coat back of a spoon).
FINISH AND SERVE: Transfer cauliflower to a plate, drizzle with balsamic-orange reduction and serve.