Cut off and discard the tough stem root of the frisee. Tear the leaves into bite-size pieces. Put the leaves in a large bowl and toss with the olive oil, vinegar and a sprinkling of salt and pepper.
Prepare the pastry by combining the flour, salt, and sugar in a food processor. Add the butter and combine until coarse crumbs are formed. With the machine running, add ice water, tablespoon by tablespoon, and keep the machine going until the dough rolls off the sides of the container into a ball. Cover the pastry with plastic wrap and refrigerate for 30 minutes. Use this time to slice the tomatoes and cheese. Roll out the dough with a little flour into a circle large enough to fit into a 10 inch tart pan or a pie pan. The dough will be about 1/8-inch thick.
Preheat the oven to 400 degrees F.
Evenly brush the mustard over the bottom of the pastry shell tucking in the edges. Cover the mustard with all the cheese, distributing it evenly. Beginning at the outer edge of the crust, make a spiral of overlapping tomato slices, working your way around to the center. In a bowl, mix the garlic, herbs and olive oil. Drizzle this mixture over the tomatoes.
Bake in preheated oven for 20 to 25 minutes or until golden brown. Remove from oven, let rest and serve atop frisee salad