Preheat the oven to 400F. Line a baking tray with parchment paper and place the tomatoes on it, cut side up. Top each with a sprig of thyme and season with pepper. Roast until soft, about 30 minutes. Remove from the oven and set aside.

Reduce the oven heat to 350F. Combine the flour, cornmeal, butter, water and salt in a food processor. Process until a dough forms. Press the dough into an 11-inch tart pan. Place a piece of parchment paper over the crust and fill with baking weights or dry beans. Bake for 15 minutes, then remove the weights and parchment paper, and continue to bake for an additional 10 minutes, or until crisp.

Place the cream cheese and eggs in a food processor and process until smooth. Stir in the basil and parmesan. Pour the mixture into the pastry shell and top with the roasted tomatoes. Bake until set, about 25 minutes.