Heat oil in large skillet. Add the yellow and red onions and saute over moderate heat 5 min. Stir in wine, add leeks. Saute another 15 min, stir frequently, or until onions are golden and leeks are limp. Remove from heat. Preheat oven 180ºC . In mixing bowl, combine beaten eggs with two tablespoons of the parsley, dill, tarragon, feta cheese, and pepper. Stir in the onion mixture. Oil a 10 in. tart pan and line bottom generously with bread crumbs. Pour in onion mixture. Ring the outside edge with tomato slice, then sprinkle the remaining parsley in the center. Sprinkle a light layer of bread crumbs over the entire top. Bake for 40 to 45 min, or until the mixture is set and top is golden. Let stand for 5 to 10 min, then cut into wedges.