Preheat oven to 425ºF. Toss tomatoes with olive oil, salt and pepper and spread in a 13 by 9-inch glass or ceramic baking dish. Roast tomatoes until they begin to burst, 20-25 minutes, stirring half way through cooking. Reduce oven to 375ºF.
Meanwhile bring large pot of water to boil and cook shells according to package directions until just tender. Drain and rinse under cold water. Combine filling ingredients and fill cooked shells evenly (about a heaping tablespoon filling per shell).
Place stuffed shells onto roasted tomatoes, nestling the shells into the tomatoes and spooning with juices. Top shells with fresh mozzarella and sprinkle with Parmesan. Cover and bake at 375ºF. for 25 minutes, remove cover and continue to bake until bubbly, 10 to 15 minutes.
Garnish with fresh basil and serve with a drizzle of balsamic vinegar glaze
Makes 4 to 6 servings.
Notes
Note: Balsamic vinegar glaze is available for purchase or you can also make your own. Some recipes add sugar, but for these shells, you can simply simmer about ½ cup good quality balsamic vinegar, uncovered, until slightly thickened.