Step 1

Heat oven to 425°F. Let butter thaw briefly if it’s fully frozen, about 5-10 minutes. In large bowl, whisk together flour, baking powder, baking soda and salt and garlic powder. Use the largest holes on a box grater to grate the butter into the flour mixture. Use fingers to toss the butter into the flour until all the butter shreds are just coated. Add the cheese and scallions and toss with fingers again to combine.

Step 2

Add 3/4 cup buttermilk to flour-butter mixture, stirring with wooden spoon or spatula gently just until dough comes together. If needed, use remaining 1/4 cup buttermilk to moisten any dry bits that won’t adhere to the dough. The dough should hold together and not be crumbly, but also not wet or sticky.

Step 3

Turn the dough out onto a well-floured surface. Very gently pat dough into 1/2-inch thick rectangle. Fold bottom third of dough up and top third of dough down over bottom third, as if folding a letter. Gently pat down into 1/2-inch rectangle again, then fold again like a letter. Pat and fold one final time, then pat dough out to 1-inch thick.

Step 4

Use floured biscuit cutter to cut dough into rounds, being careful not to twist biscuit cutter when removing the rounds (alternatively, you can cut the dough into squares with a knife if you don’t have a biscuit cutter or round cookie cutter). Gather dough scraps and gently pat into 1-inch thick mass, then cut again to use up all the dough.

Step 5

Place rounds, sides gently touching, on baking sheet or in cast-iron skillet. Brush egg wash over biscuits. Bake 13-15 minutes until golden brown on top.