Preheat the oven to 450º F.

Combine flour, baking powder, sugar, and salt in a mixing bowl. Whisk to combine.

Use a food processor or grater to grate frozen butter. Add grated butter to flour mixture. Mix butter and flour together, until it resembles small crumbs.

Use a fork to smash 1/3 of the blueberries then toss all of the blueberries into the flour. Mix to distribute blueberries throughout the flour.

Add very cold buttermilk to the flour and stir/knead this until the milk is fully incorporated. Form a ball of dough (it will be slightly wet) then empty the dough onto a floured surface. Add more flour on top of the dough and continue kneading for 60 seconds.

Lightly coat a rolling pin with flour and use it to roll out to a rectangle that is approximately 9x12”. Use a biscuit or cookie cutter to make uniform biscuits.

Spray baking sheet with nonstick spray or smear butter onto the pan before baking. Bake for 20 - 25 minutes, depending on the size of the biscuits and your preferred doneness. The larger your biscuits, the longer they will take to bake.