Preheat the oven to 450 degrees. Marinate the zucchini in vinaigrette for 10 minutes at least. Remove the portobello stems. Then, very carefully, slice them in half horizontally so you end up with two 8 large rounds. Set the rounds on a baking sheet and spread each round with some olivada and about a tablespoon of cheese. Add the marinated zucchini strips to the baking sheet and roast for 10 minutes. Remove the mushrooms and zucchini from the oven and assemble. Set a portobello round on the bottom of a dinner plate and top with zucchini, cover with another portobello round and cover with zucchini. Garnish the top and sides with tomato salsa, chives and black olives slices.