1. Preheat grill to medium (300 - 350F). Cut a 1/8 inch slice across the stem end of each tomato. Core and seed tomatoes; place them upside down on several layers of paper towels. Let stand for 30 minutes.
2. Brush corn with 1 tablespoon of the oil. Place corn on grill; grill, uncovered, 4 to 5 minutes or until tender, turning often. Let cool.
3. When cool enough to handle, cut corn from cob into a large bowl. Add bell pepper, feta, green onions, basil, vinegar, remaining 4 tablespoons oil, and salt andpepper to taste, toss to combine. Fill tomatoes with corn mixture, and serve.
2. Brush corn with 1 tablespoon of the oil. Place corn on grill; grill, uncovered, 4 to 5 minutes or until tender, turning often. Let cool.
3. When cool enough to handle, cut corn from cob into a large bowl. Add bell pepper, feta, green onions, basil, vinegar, remaining 4 tablespoons oil, and salt andpepper to taste, toss to combine. Fill tomatoes with corn mixture, and serve.