Preheat oven to 450°F. Arrange oven racks to bottom half of oven.

Use two baking sheets. In one pan, toss broccoli with 2 T, salt and pepper. In second pan, toss cauliflower with 1 T oil, salt and pepper.

Roast 30-35 min, until tender. Rotate pans between racks half way through roasting.

In medium bowl, add 1/2 tsp orange zest and 1/4 c juice. Add 1/4 tsp lemon zest and 2 T juice. Whisk in 2 T oil, salt and pepper.

Arrange broccoli and cauliflower on serving dish. Scatter olives over veggies. Whisk dressing and drizzle over veggies. Garnish with parsley.