Preheat oven to 475 F (245 C).

Weigh your flour. Grate frozen butter into the sifted self-rising flour. Stir to combine until the butter is fully coated by flour.

Put the bowl in the freezer for 10 minutes. It's important to keep the butter as cold as possible through this process. 

Combine lemon zest, ground black pepper, and buttermilk with the cold flour/butter to bring it together as a dough. Stir no more than 15 times. Overworking the dough at this stage could cause your finished biscuits to be more tough. Your dough at the end of 15 stirs will be very shaggy and not smooth at all. 

On a floured surface dump out dough and roll with a rolling pin. If you don't have a rolling pin, you can just use your hands. Dust with flour as needed when the dough gets sticky. Fold the dough over on itself five different times. This folding process is what creates the layers in the biscuits. 

Roll or flatten the dough to 3/4 to 1 inch thick/tall.

Cut biscuits into circles or squares and place on a parchment paper-lined baking sheet. When cutting, you do not want to twist the cutter or knife. Twisting while cutting will ruin the layers that you created with folding. Place your cut biscuits next to each other (touching) on the sheet pan. Touching biscuits help each other rise taller. 

After cutting biscuits, you can grab any scraps of dough and reroll and re-cut them. There's no need to waste any dough. The last few biscuits might not look as uniform as the first ones, but they will all taste the same. 

Bake at 475 degrees F (245 C) for around 15 to 20 minutes. Check around the 12-minute mark to make sure they do not brown too much.

When biscuits are done, transfer them from your baking pan onto a cooling rack to stop the bottoms from cooking further.

Paint the melted butter on top of each biscuit and then top the melted butter with a pinch of lemon zest and ground black pepper. 

Serve and enjoy.