Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper or lightly grease it.
In a large mixing bowl, cream together the softened butter and grated cheddar cheese until well combined.
Gradually add the flour, salt, and chopped jalapeños to the mixture, stirring until a dough forms. You may need to use your hands to knead the dough together until smooth.
Roll the dough into a log shape, about 2 inches (5 cm) in diameter.
Wrap the log of dough in plastic wrap and refrigerate for at least 30 minutes to firm up.
Once chilled, slice the dough into rounds, about 1/4 inch (0.6 cm) thick, and place them on the prepared baking sheet, leaving some space between each cookie.
Bake in the preheated oven for 12-15 minutes, or until the edges are lightly golden.
Remove from the oven and allow the shortbread to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.
