In a bowl, mix together the corn, red onion, cumin, chile, garlic, and oil. Spread the vegetable mixture onto a baking pan and roast about 3 inches from the flame or heat source for about 10 minutes, stirring often. When the corn is beginning to brown, remove from the oven and set aside to cool.
Combine the avocado, tomato, lime juice, vinegar, and cilantro in a mixing bowl. Stir in the vegetable mixture and add salt and pepper to taste. Serve immediately.