Preheat the oven to 350 degrees F (180 degrees C).
Thinly slice the Red Potato (1 pound) using a mandolin or sharp knife—they should be 1/8 inch thick or thinner.
Place them in a large bowl and toss them with Extra-Virgin Olive Oil (to taste) and with Kosher Salt and Freshly Ground Black Pepper (to taste).
Line the quiche pan with the potatoes, overlapping them as you arrange them. Be sure the layer of potatoes closest to the edge extends above the rim.
Place the pan on a sheet pan and transfer to the oven. Bake for 20 minutes.
Meanwhile, place Large Egg (1) and the All-Purpose Flour (3 tablespoon) in a large bowl and whisk until smooth.
Whisk in the remaining Large Egg (4) untl blended.
In a medium bowl, whisk the Crème Fraîche (1 cup) until smooth. Whisk in the Whole Milk (1 cup). Pour the egg mixture through a fine mesh sieve held over the milk mixture.
Whisk in the Kosher Salt (1 teaspoon), Freshly Ground Black Pepper (1/2 teaspoon), Fresh Chives (1/2 cup), Fresh Thyme (2 teaspoon), and Tarragon (1/4 cup).
Pour the egg mixture into the pre-cooked potato crust.
Reduce the oven temperature to 325 degrees F (160 degrees C) and bake until the filling is just set, about 40 minutes. The center of the quiche should still feel slightly firm, rather than liquidy, when touched.
Let cool on a wire rack for at least 20 minutes to allow the custard to set up, so that it will slice neatly.
It can be served warm or at room temperature. To serve a fully cooled quiche warm, cover it with aluminum foil and reheat it in a 325 degrees F (160 degrees C) oven for about 15 minutes.