Pre-heat oven to 400 degrees.
In a large bowl, whisk together flour, sugar, baking powder, cream of tartar, garlic powder, salt, and pepper.
Work butter into the flour mixture, using a pastry blender or your fingers. Blend until the mixture is coarse.
Mix in chopped jalapeño peppers and chives.
In a separate small bowl, whisk together buttermilk and egg.
Pour buttermilk mixture into flour mixture, stirring with a wooden spoon until just combined, taking care not to over-mix.
Scoop about ½ cup of the dough with a measuring cup or ice cream scoop onto a parchment-lined baking sheet, placing scoops about 2 inches apart.
Bake biscuits at 400 degrees for 19-22 minutes, until just starting to brown.
Let cool in pan for about 5 minutes before moving to wire rack to cool completely.