Preheat the oven to 425°F. In a large bowl whisk together the flour, cayenne, black pepper, baking powder, and salt. Set aside.

Dice the butter into small pieces. If they get too warm then place them in a bowl and put it in the freezer for about 10 minutes before continuing.

Toss the diced butter with the flour mixture until well coated. Add the scallions and cheese and toss until well coated.

Add the buttermilk and mix with your hands until it just comes together. You may find you need an extra dribble of buttermilk, if so then go right ahead but do so judiciously. Do not over-knead.

Roll the dough out onto a lightly floured surface. Knead once or twice; no more. Form into an 8x8-inch square and cut into 2x2-inch squares and top with a bit of high-quality salt if using.

Bake for 12-16 minutes or until golden.