From America's Test Kitchen Season 4: Summer Tomatoes
Falling somewhere in between pizza and quiche, tomato and mozzarella tart shares the flavors of both but features unique problems. For starters, this is not fast food, as some sort of pastry crust is required. Second, the moisture in the tomatoes almost guarantees a soggy crust. Third, tomato tarts are often tasteless, despite their good looks, falling short on flavor. We wanted a recipe that could easily be made at home with a solid bottom crust and great vine-ripened flavor.
Frozen puff pastry was the solution to an easy crust, and prebaking it was a start—but only a start—to solving the problem of sogginess. Sealing the puff pastry shell with an egg wash helped. Yet even with these preventive measures, the tomato juice still found its way into the crust. To extract more moisture from the tomatoes before baking the tart, we sliced and salted them, then pressed them lightly between paper towels. This removed much of the moisture. But even with a layer of grated mozzarella cheese (whole milk worked best) between tomatoes and crust, the tart shell still came out a bit soggy. Our breakthrough came when we added a layer of grated Parmesan cheese, which sealed the crust fully and repelled moisture. After a short stay in the oven, our tart had a crisp and sturdy crust, nutty flavor from the Parmesan, and rich flavors from the cheese and tomatoes.
Serves 6 to 8
Thawing the frozen puff pastry in the refrigerator overnight will help prevent cracking while unfolding it. Be sure to use a low-moisture supermarket mozzarella sold in block form, not fresh water-packed mozzarella. If you prefer to do some advanced preparation, the tart shell can be prebaked through step 1, cooled to room temperature, wrapped in plastic wrap, and kept at room temperature for up to two days before being topped and baked with the mozzarella and tomatoes.