- Place mushrooms in a large bowl with onion wedges. Add 4 tbsp olive oil; sprinkle with salt and pepper to taste. Toss well.
- Arrange in a single layer on large shallow baking pan and roast uncovered on bottom shelf in 240°C oven for 15 minutes; stir and continue to roast for another 15 –20 minutes.
- Meanwhile cut zucchini in half lengthwise and then crosswise in 3cm pieces and place in the same bowl and add tomatoes; toss with remaining olive oil and salt and pepper to taste.
- Place tomatoes cut side up on another baking sheet with zucchini and roast in oven with mushrooms for 15-20 minutes or until softened and sizzling.
- Remove vegetables from oven and spoon into large serving bowl.
- In measuring cup combine vinegar, basil, garlic, hot pepper flakes and parsley (if not using fresh basil) and pour over warm vegetables. Toss lightly; serve at room temperature as side dish or on grilled polenta for main course.
Tip: In barbecue season, place vegetables in shallow metal pans and roast with lid closed.
Grilled Polenta: Purchase pre-cooked polenta rolls and cut into ½ inch thick rounds or prepare your favorite polenta and chill until firm in square pan and cut out squares. Brush with olive oil and grill, broil or bake until golden brown.