01 - Preheat oven to 400°F. Grease a standard 12-cup muffin tin or line with paper liners.
02 - In a large mixing bowl, whisk together all-purpose flour, baking powder, baking soda, salt, chili powder, and garlic powder until thoroughly combined.
03 - Add cold cubed unsalted butter. Cut into flour mixture using a pastry cutter or fork until the mixture resembles coarse crumbs.
04 - Fold in shredded sharp cheddar cheese, finely diced jalapeños, minced garlic, and chopped fresh chives.
05 - Pour in buttermilk. Gently mix until just combined and a sticky dough forms. Take care not to overmix.
06 - Using a large spoon or cookie scoop, divide dough evenly among prepared muffin cups, forming rounded balls.
07 - Place muffin tin in oven and bake for 16 to 18 minutes, or until tops are golden brown and a toothpick inserted in the center of a muffin ball comes out clean.
08 - Remove pan from oven and immediately brush tops with melted butter. Sprinkle chili flakes over each ball if desired. Allow to cool for 5 minutes before transferring to a cooling rack. Serve warm.