6tablespoonsunsalted butter, cold and cut into cubes (85 grams)
1cupcheddar cheese, shredded (113 grams)
1-2jalapeñosthinly sliced (see Note)
¾cupcold buttermilk, plus additional for brushing (175 ml)
Preheat oven to 400°F. Line a sheet pan with parchment paper.
In a medium bowl mix together the flour, cornmeal, baking powder, baking soda, and salt. Mix in the butter with a pastry cutter or a fork until mixture resembles coarse meal. Add ¾ cup of the cheese and the jalapeño slices. Add the buttermilk and stir until the dough comes together in a ball.
On a lightly floured surface, gather the dough into a bowl and knead gently 6 times. Pat dough to about ½ inch thick. Cut dough into three inch rounds with a lightly floured cutter. Place on the prepared baking sheet about 2 inches apart. Brush with buttermilk and top with remaining cheese.
Bake until golden brown, about 15-20 minutes. Transfer to a wire rack to cool. Store leftovers in an airtight container at room temperature for up to 3 days.
Note: Use 1-2 jalapeños depending on how spicy you'd like the biscuits. If desired, remove the seeds before adding them to the recipe.