Prepare the Dough

1. Preheat Oven: Preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper.
2. Mix Dry Ingredients: In a large mixing bowl, whisk together the flour, baking powder, and salt.
3. Cut in the Butter: Add the cold, cubed butter to the flour mixture. Using a pastry cutter or your fingers, cut the butter into the flour until it resembles coarse crumbs.
4. Add Cheese and Jalapeños: Stir in the shredded cheddar cheese and chopped jalapeños until well combined.
5. Add Milk: Gradually add the milk to the mixture, stirring until just combined. Be careful not to overmix.

Shape and Bake the Biscuits

1. Turn Out the Dough: Turn the dough out onto a lightly floured surface. Pat it into a rectangle about 1 inch thick.
2. Cut the Biscuits: Using a biscuit cutter or a knife, cut out biscuits from the dough and place them on the prepared baking sheet.
3. Bake: Bake in the preheated oven for 15-20 minutes, or until the biscuits are golden brown on top.