Preheat the oven to 425 degrees F. Place the cast iron skillet in the preheating oven to preheat as well.
In a large mixing bowl combine flour, baking powder, salt and pepper. Mix to combine. Then add cold butter and use your hands to pinch it into the flour mixture until a fine, sandy texture is achieved. *(Do not overwork or melt the butter. There should still be small pieces of butter present throughout.)*
In a separate mixing bowl whisk together eggs and buttermilk until frothy. Then add in shredded cheese and minced jalapenos and mix to combine.
Use your hand to form a well in the center of the flour mixture. Pour the egg and buttermilk mixture into the well and use 2 knives (or a fork) to cut the mixture together.
Pour the dough onto a floured surface and use you hands to gently press flat. Then fold the dough horizontally like an envelope and press flat, fold vertically and press flat. Repeat this 2-3 times then use a rolling pin to gently roll out the dough to 1 ½ inch thickness. Use a biscuit cutter to cut out about 12 biscuits. Arrange the biscuits in the preheated cast iron skillet. Then brush the tops with a little buttermilk and a slice of jalapeno.
Bake the biscuits at 425 degrees F for 20-25 minutes until golden brown. Remove from the oven and brush the tops with a little melted butter. Then sprinkle on some flaky sea salt. Enjoy!