Preheat the oven to 375 degrees F.
Line the shell with foil and fill with pie weights, dried beans, or rice. Bake in the lower third of the oven for 20 minutes. Carefully remove the weights and foil. Return to the oven and bake for 10 minutes more or until light golden. Cool in the pan on a wire rack.
Turn up the oven to 400 degrees F.
Sprinkle the tomatoes with salt and drain in a colander for 10 to 15 minutes. Spread the mustard over the bottom of the shell and sprinkle the cheese over it. Arrange the tomatoes over the cheese in 1 overlapping layer. Bake until the pastry is golden brown and the tomatoes are very soft, 35 to 40 minutes.
In a small bowl, stir together the parsley, thyme, garlic, olive oil, and salt and pepper to taste to blend. Sprinkle the pie with this mixture while hot and spread out gently with the back of a spoon. Serve the pie hot or at room temperature.
Recipe courtesy of Sara Moulton, Sara Moulton Cooks at Home, Broadway Books, 2002