Preheat the oven to 400. Lightly grease a baking tray with shortening or baking spray and set aside. In a medium bowl, add the flour, baking powder and salt and stir to combine.
Using a box grater, grate the cold butter into the flour and toss it gently with your hands to separate the pieces.
Add the milk and use a fork to stir until no pockets of flour remain. Your batter should be fairly soft. Lightly flour your work surface then scrape your dough out.
Gently fold the dough over onto itself two to three times, then flatten into a 1-inch thick circle.
Using a 2 or 3 inch biscuit cutter, cut circles and place them on your baking tray. You can place them touching for softer edges, or an inch apart for crispier edges.
Bake for 20 minutes until the edges and bottoms are just golden brown, checking them at 17 minutes, just in case.
Make the Gravy
While the biscuits cook, make the gravy: heat a 9-inch cast iron or other heavy bottomed skillet over medium-high heat and add your sausage, reduce heat to medium and crumbling until it's in small pieces and no pink remains--about 6 minutes.
You need about 2 tablespoons of sausage drippings in your pan. If you have more than that, drain out any extra. If you don't see much grease, that's okay--there's still some in there. Just go with it.
Add the flour and stir to combine with the sausage and the flour cooks slightly--1 minute.
Reduce heat to medium, pour in the milk and stir to combine. Add the salt and pepper (add half the salt first, taste it and then add the rest if needed) Stir gently but constantly, making sure to scrape the bottom as you stir, raising the heat slightly if needed.
The gravy will come to a slow simmer with bubbles around the edges. Cook until thickened enough to coat the back of a spoon about 7 or 8 minutes or to your desired consistency. (remember the gravy will thicken further as it cools)