In a heavy skillet, heat the oil over medium-low heat. Saute the onions for 5 to 6 minutes, or until softened. Add the chiles, tomatoes, and salt to the pan and increase the heat to medium-high. Continue cooking for about 10 minutes, stirring frequently, until most of the liquid has evaporated. Set aside and allow to cool completely. In a large covered vegetable steamer, steam the zucchini for 5 to 6 minutes, or until tender but. not mushy. Season to taste, then remove the steamer from the pan and let them cool completely. Preheat the oven to 350 degrees and thoroughly butter a medium oven-proof casserole or souffle dish. Coat the inside of the dish with the bread crumbs. In a large mixing bowl, whip the egg whites with 1/4 teaspoon salt to stiff peaks, then add the egg yolks, beating them in well. The mixture will be frothy but stiff. Distribute a layer of zucchini slices in overlapping circles on the bottom of the casserole. Pour half of the sauce over the top in an even layer, then distribute 1/3 of the cheese over it. Cover the cheese with 1/3 of the beaten egg mixture, then dot with 1 tablespoon of the butter cut into tiny pieces. Repeat the layering in the same order and finish with a layer of zucchini topped with the last 1/3 of the beaten egg, butter, and cheese. Cook the torte on the top shelf of the oven until the eggs are set and the cheese has melted, about 25 to 30 minutes. Remove from the oven, let rest for 5 minutes, and serve.
Fresh chiles and bell peppers can be roasted over a gas flame or on a tray under the broiler. Keep turning so the skin is evenly charred, without burning and drying out the flesh. Transfer the charred peppers to a plastic bag, tie the top closed and let steam until cool to the touch, about 15 minutes. (If you are rushed, you can place the bag in a bowl of iced water to speed things up.) The best way to peel is just to pull off the charred skin by hand and then dip the peppers briefly in water to remove any blackened bits. Do not peel the pepper under running water since that it will wash away flavorful juices. Once peeled, cut away stems, seeds and veins.
c.1997, M.S. Milliken & S. Feniger, all rights reserved