Preheat oven to 450 degrees F.
Grease the bottom and side of a 9-inch springform pan with cooking spray. Cut parchment paper in a circle the diameter of the bottom and another to fit the sides of the pan (one circle and one long rectangle). Line the pan with the parchment, then spray the parchment with more cooking spray. You can also just use a standard 9-inch pie pan and serve it right out of the pan (so you can skip the parchment step). The springform pan just makes a more dramatic presentation.
Place the grated sweet potatoes in a large piece of cheesecloth or a clean kitchen towel. Gather corners together and squeeze out any moisture.
In a medium bowl, whisk together 1 egg, 2 teaspoons salt, 1 teaspoon black pepper & a pinch of crushed red pepper flakes. Add the squeezed sweet potatoes and mix to totally combine. Press the sweet potato mixture into the bottom and up the sides of the prepared pan. Place on a rimmed cookie sheet and bake for 30 minutes. Remove from oven and allow to cool slightly, about 10 minutes.
Turn oven down to 350 degrees F.
Meanwhile, heat the butter over medium high heat. Add the leeks, along with a pinch of salt and pepper and cook until softened, about 6-8 minutes. Let cool slightly before adding to the egg mixture.
For the egg mixture, whisk together the eggs, salt, pepper, and coconut milk or cream until totally smooth. Add the cooled leeks and ½ the goat cheese. Stir to combine. Pour the filling into the prepared crust. Sprinkle the rest of the goat cheese on top.
Bake 30 minutes, until the center is mostly set. Allow to rest 20 minutes before serving. Serve at room temperature. Enjoy!