Place onion, pumpkin, baby marrows, tomatoes and rosemary sprigs in a large roasting pan. Mix the olive oil, Spur BBQ Sauce and sugar and pour over vegetables.
Roast at 200°C for 20 minutes, stirring occasionally. Place rocket leaves onto a serving dish and top with roasted vegetables.
Dressing: Mix all ingredients together, drizzle over salad and serve immediately.