Preheat the oven to 425F. Stretch the puff pastry into an 8 - inch pie plate, trimming and saving any extra edges for another use. Place a smaller dish inside the pie plate on top of the pastry with pie weights or dried beans. Bake the pastry crust for 10 minutes, then remove from the oven to cool. Reduce the oven heat to 375F.

Meanwhile, prep the filling. Cut the bacon into small bits, then fry in a skillet over medium heat. Remove from the pan and drain on paper towels.

Cut the asparagus into 1-inch or so pieces. Bring a few inches of salted water to a boil, and boil the asparagus for 2 minutes, then drain.

Combine the cornstarch and milk together well in a large bowl. Add the eggs, half the cheese, scallions, crispy bacon, a sprinkle of salt, and lots of black pepper. Whisk to combine.

To the partially cooked crust, add the remaining cheese to form a barrier between the egg filling and the crust. Top the cheese with the asparagus. Pour the egg mixture over the asparagus.

Bake the quiche at 375F for 20 - 30 minutes until the egg is no longer jiggly when you shake the quiche and the crust is browned. Let rest for 15 minutes, then cut into wedges and serve!