1 sheet (from 1 pound (450 g pkg) frozen butter puff pastry, thawed
8 red or striped heirloom plum tomatoes, about 1 ¼ pounds
1 cup yellow teardrop or cherry tomatoes halved lengthwise
2 tbsp extra virgin olive oil
1 clove garlic, minced
½ tsp salt
¼ tsp pepper
1 egg beaten
1 cup shredded Gruyere cheese
2 tsp fresh thyme or oregano
Line 2 rimmed baking sheets with parchment paper; set aside.
On lightly floured surface, roll out pastry to 10-inch square; transfer to prepared pan. Using fork, prick pastry all over; refrigerate for 30 minutes.
Meanwhile, cut red tomatoes crosswise into ½ -inch thick slices. In bowl, toss together red and yellow tomatoes, oil, garlic, salt and pepper; spread on remaining prepared pan. Roast in 400F oven until slightly charred and shriveled, about 30 minutes. Let cool on pan.
Bake pastry in center of 400 degrees F. oven until light golden and puffed, 12 to 15 minutes. Let cool slightly. Brush pastry all over with some of the egg; sprinkle with cheese, leaving a 1-inch border. Arrange red tomatoes in overlapping rows on cheese. Scatter yellow tomatoes over top; sprinkle with thyme. Return to oven and bake until golden and puffed, 12 to 15 minutes. Let cool for 5 minutes; cut into squares. Serve warm or at room temperature.
Adapted from Canadian Living August 2007