mathilde’s tomato tart

Make the dough: Place flour, sugar, salt, and butter in a food processor. Pulse until mixture resembles coarse crumbs. Add egg and water to the food processor, pulsing to incorporate. Pulse until dough comes together. Turn out dough onto a sheet of parchment and shape into a disk. Place another sheet of parchment on top and roll out to an 11-inch disk. Slide onto a plate or tray and freeze for 10 minutes, until firm but not so hard that it will crack when bent. Line a 9.5-inch tart pan, preferably one with a removable bottom, with the dough. [A pie dish or cake pan lined with parchment could work as well, just keep the sides 1-inch high.] Trim excess dough (reserve in the fridge for patching) and prick the bottom with a fork. Freeze for 20 minutes, until solid. Bake shell: Preheat the oven to 375ºF with rack in center. Place the tart pan on a rimmed baking sheet. Weigh the crust down with parchment paper and pie weights, dried beans, or rice (that you don’t plan on using for anything else). Bake crust for 20 minutes. Remove parchment and weights. If there are any cracks or breaks, you can patch with the remaining dough. Bake for 5 minutes more. Remove from oven and let cool.Make the filling: Meanwhile, place tomato slices on a rimmed baking sheet and lightly sprinkle with salt.Combine garlic, parsley, basil, and ½ teaspoon salt in a food processor. Pulse until finely chopped. Add olive oil and pulse until a spreadable paste forms. You might need to scrape down the sides of the food processor a few times. If making the herb mixture in advance, store in the refrigerator with plastic wrap pressed against its surface.Blot tomatoes with paper towels to remove excess liquid.Using a small spoon or offset spatula, spread Dijon mustard evenly on the bottom of the crust. Evenly distribute cheese on top. Dollop with herb mixture and gently spread to cover in a thin layer. Top with tomatoes, overlapping. Cut smaller pieces of tomatoes to fill gaps. The tomatoes shrink while roasting, so keep them snug and the tart pan full. Lightly brush tomatoes with olive oil and sprinkle with freshly ground pepper.Bake tart: Until tomatoes are softened and the crust is golden, about 50 minutes and up to 1 hour, until the tomatoes are deeply roasted. Allow to cool slightly then serve warm or at room temperature. Do ahead: You can make the dough a few days in advance and refrigerate. You can also bake the crust one day and make and bake the filling another, as I did. Leave at room temperature; no need to wrap. Leftovers of the finished tart keep in the fridge for 4 to 5 days.