• Boil the potatoes. Cut the potatoes in half and place them in a large pot of salted water. Bring to a boil and cook until fork tender, about 20 minutes.
  6 medium Yukon Gold potatoes
• Prepare the potatoes. Drain the potatoes and let them cool until they're comfortable to handle. Leave the skins on for a rustic crust, or peel them for a smoother finish.
• Prepare the pan. Preheat the oven to 425°F (220°C). Lightly coat a springform pan with olive oil spray.
• Build the crust. Press the peeled potatoes evenly across the bottom and up the sides of the pan. Use the bottom of a measuring cup or drinking glass to firmly compress the potatoes into an even crust.
• Pre-bake the crust. Spray the potato crust lightly with olive oil and sprinkle with salt. Bake for 20 to 25 minutes, until lightly golden and beginning to crisp.
  1 teaspoon kosher salt, Olive oil spray
• Cook the mushrooms. While the crust bakes, heat the butter or olive oil over medium heat. If using king trumpet mushrooms, brown the cut sides until deeply golden, then briefly cook the second side until just tender. For other mushroom varieties, sauté for about 5 minutes, until tender and lightly browned.
  8 ounces King Trumpet Mushrooms
• Layer the filling. Scatter the spinach, chives, parsley, and goat cheese over the baked potato crust. Spoon the sautéed mushrooms evenly across the top.
  1 bunch fresh chives, 4 sprigs fresh parsley, 2 cups baby spinach, 3 oz goat cheese
• Mix the custard. Whisk together the eggs, heavy cream, salt, black pepper, and red chili flakes until smooth.
  8 large eggs, 1 ½ cups heavy cream, 1 teaspoon kosher salt, ¼ teaspoon freshly ground black pepper, ½ teaspoon red chili flakes
• Fill the quiche. Slowly pour the egg mixture over the vegetables and cheese, allowing it to settle evenly throughout the crust.
• Bake until set. Reduce the oven to 350°F (177°C). Return the quiche to the oven and bake for 55 to 60 minutes, until the edges are set and the center has just a slight wobble. It will continue to set as it rests.
• Rest and serve. Let the quiche cool for 10 minutes before removing the springform ring. Finish with fresh chives and flaky sea salt before serving.

The Quiche