In a small saucepan of boiling water, blanch the garlic for 3 minutes. Drain and, when cool, cut into slivers. In a small bowl, whisk together the vinegar, salt, pepper, cumin, and cayenne and add the olive oil in a thin stream, whisking all the time until emulsified. Stir in the shallots and green onions.
Toss the tomatoes, blanched garlic, chiles, and peppers together on an oval or round ceramic platter. Drizzle the dressing over, toss again, and scatter on the crumbled cheese.
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 will wash away flavorful juices. Once peeled, cut away stems, seeds and veins.
c.1997, M.S. Milliken & S. Feniger, all rights reserved