Preheat oven to 450 F.

Add flour into a large bowl.

Grate the frozen butter into the flour.

Using a pastry cutter, cut in the butter until the mixture resembles coarse crumbs.

Pour in the cold buttermilk and stir with a rubber spatula until a dough forms.

Lightly flour a work surface, and turn the dough out onto the work surface.

Flour your hands and gently knead the dough, adding more flour as needed but not too much. Dough should be slightly sticky.

Fold the dough several times to create layers, working quickly to prevent the dough from warming.

Finally, pat the dough into a 1-inch thick rectangle.

Using a 3-inch biscuit cutter, cut out 4 biscuits. Regather the dough and pat it back out to cut the remaining biscuits.

Place biscuits on a baking sheet, with the sides touching.

Bake for 12-14 minutes.

Brush the tops lightly with extra melted butter during the last minute or two and switch the oven to broil to brown the tops if needed.

As soon as biscuits come out of the oven, brush with melted butter twice, allowing it to absorb between brushing.