Preheat oven to 425° (220°C). Combine cauliflower, bell pepper, shallots and 1 Tbsp. (15 mL) Becel® with Avocado Oil margarine on jelly-roll pan or rimmed baking sheet. Roast until cauliflower is browned and slightly crispy, about 25 minutes.
Meanwhile, cook quinoa according to package directions. Fluff with fork and spoon into large bowl. Toss with cauliflower mixture and remaining ingredients.