1. Preheat oven to 425° (220°C). Combine cauliflower and 4 tsp (20 mL) margarine and arrange on two-thirds of jelly roll pan or rimmed baking sheet.
2. Combine red onion and 2 tsp (10 mL) margarine and arrange on remaining third of jelly roll pan. Roast until cauliflower is browned and slightly crispy and onion is tender; about 25 minutes.
3. Meanwhile, cook quinoa according to package directions. Fluff with fork and stir in mint. Combine remaining 2 tbsp (30 mL) margarine, turmeric, cumin and red pepper flakes and stir into quinoa. Divide between four bowls. Evenly top each bowl with cauliflower, red onion and avocado.