Preheat a broiler or prepare a charcoal fire and let burn to a gray ash. Place corn on a broiling pan or grill set about 6 inches from heat source. Cook, turning often, until kernels have softened and are lightly browned, about 10 minutes. Let cool, then cut off kernels from each ear (you'll have about 3 cups).
In a large bowl, combine corn kernels, tomatoes, onions, olive oil, vinegar, salt, pepper and Tabasco sauce. Add parsley and stir well. Chill until ready to serve.