Combine all the pie crust ingredients in a food processor fitted with the steel blade. Pulse until it all comes together into a ball of dough. Wrap in plastic wrap and chill in the refrigerator for at least 30 minutes. (Can be made 1 day in advance.)

In a large skillet, heat the olive oil over medium-high heat. Once hot, add the chard and sauté until wilted. Remove from the pan and place on a paper towel to drain.

Once the dough has chilled, roll it out between 2 sheets of plastic wrap until ¼- to ½-inch thick. Peel off the top layer of plastic wrap and transfer the exposed side down into a 9-inch pie plate. Peel off the other layer of plastic wrap and use damp fingers to gently press the dough down into the plate, making sure to fill in any gaps. Mold the edges of the pie crust with your fingers, trimming off any excess dough and using it to repair any gaps.

Preheat the oven to 350°F. Arrange the chard, smoked salmon, goat cheese, and tomato slices in the pie shell. In a medium mixing bowl, whisk together the eggs, milk, Parmesan, Herbes de Provence, salt, and pepper. Pour into the pie shell over the other ingredients. Gently cover the edges of the quiche with aluminum foil. Bake for 40 minutes or until the quiche has begun to set. Remove the foil and continue to bake until the quiche has fully set and the crust has browned, about 15-20 more minutes depending on the depth of the baking dish. Serve warm.