1. Preheat oven to 425 degrees Fahrenheit and pour two tablespoons extra virgin olive oil on two large baking pans. Heat up oil for five minutes (careful to do this far from the heating element).
2. Place the prepared vegetables on trays according to the list above. Separately, combine the remaining two tablespoons olive oil and seasonings. Pour half over each tray.
3. Roast tray one for 15 minutes and tray two for 20 minutes.
4. While vegetables are roasting, place dressing ingredients in a food processor. Process until combined.
5. Layer vegetables on an open platter and pour green tahini dressing on top.