Partially mash beans in a medium sized mixing bowl (they should remain slightly chunky). Heat oil in a medium sized saucepan, on medium heat. Mix in onion, garlic and sauté for 4 minutes. Add beans, corn, tomato, Picante sauce, cumin, chili powder and cook for 5 minutes (or until thickened). Remove the pan from heat, and stir in cheese, cilantro and lime juice. Continue stirring until the cheese has melted, and serve.