01 -
In a large pan, cook the sausage over medium heat, breaking it apart into small pieces. Once browned, sprinkle with flour, stir it in well, and let it cook for a couple of minutes.
02 -
Slowly add the milk while stirring it in nonstop. Turn up the heat a little to medium-high to bring it to a boil. Lower the heat and let it simmer until it gets thick, which should take around 5 minutes. Toss in the salt, black pepper, sage, and red pepper flakes if you like.
03 -
Set the oven to 375°F (190°C). Roll out one sheet of puff pastry and lay it in a 9-inch pie dish, letting the edges hang over slightly.
04 -
Spoon the sausage gravy into the dish with the puff pastry, spreading it evenly. Take the second sheet of pastry and roll it out, placing it on top. Trim any extra dough around the edges and pinch them to seal everything up. Cut a few small slits in the top to let steam escape.
05 -
Put the pie on the center rack of the oven and bake for 25-30 minutes or until the top is golden and crispy. Let it rest for a few minutes before cutting into slices to serve warm.