Preheat your oven to 425°F (220°C) and line a baking sheet with parchment paper.

In a large mixing bowl, whisk together the all-purpose flour, baking powder, and salt.

Add the cold, cubed unsalted butter to the flour mixture. Using a pastry cutter or your fingers, mix until the mixture resembles coarse crumbs.

Fold in the shredded cheddar cheese and finely chopped jalapenos until evenly distributed.

Pour in the buttermilk and mix until just combined. Be careful not to over-mix; the dough should be slightly sticky.

On a floured surface, turn out the dough and gently pat it down into a rectangle about 1-inch thick. Cut out biscuits using a round cutter or a glass, and place them on the prepared baking sheet.

Alternatively, you can drop spoonfuls of dough onto the sheet for a more rustic look.

Bake in the preheated oven for 12-15 minutes, or until the biscuits are golden brown.

Let them cool slightly, then serve warm, maybe with a pat of butter or your favorite spread!