Preheat oven to 425°F. Place broccoli florets in a medium saucepan with a bit of water (or in the microwave) and cook until barely fork-tender, about 4 minutes. Run under cold water to stop the cooking and roughly chop. In a medium bowl, whisk milk, eggs, salt, and pepper. Set aside.
Line a 9-inch pie plate with store-bought or homemade pie crust and crimp the edges.
In a medium bowl whisk milk, eggs, salt, pepper, and red pepper flakes. Stir in the broccoli and set aside.
In the bottom of the crust-lined pie plate, layer cooked bacon, cheddar, and scallions. Pour the egg and broccoli custard over the top.
Bake 15 minutes at 425 degrees. Without opening the oven, reduce the temperature to 325 degrees and continue to bake for another 20 to 25 minutes, or until a knife inserted in the middle comes out clean. Cool 10 minutes before cutting into wedges.
Notes
Simple Single-Layer Homemade Pie Crust
1 1/4 cup all-purpose flour
1/2 teaspoon salt
1/2 teaspoon sugar
1/2 cup (1 stick) cold unsalted butter, cubed
2 tablespoons water
Whisk the flour, salt, and sugar in a bowl. Cut in the cubed butter until it resembled coarse crumbs. Add 2 tablespoons of iced water. Using a fork, pull the ingredients into a shaggy dough. Add up to an additional 2 tablespoons of iced water if necessary. Transfer shaggy dough onto a piece of plastic wrap. Use the wrap to flatten and press dough together. Chill until firm; 2 hours or up to 3 days.When ready to bake, roll out the dough to fit a 9-inch pie plate. Crimp the edges, line the dough with parchment paper and fill with pie weights or beans. Blind bake the crust at 375 degrees for 10 minutes. Remove the weights and prick the bottom of the crust generously with a fork. Bake for another 5 minutes. Remove the crust from the oven and let cool before filling with custard.