Preheat oven to 400ºF. Grease muffin tin (for 12 muffins) with shortening or cooking spray. Place all dry ingredients in a medium sized mixing bowl and blend well. Add buttermilk, egg, vegetable oil, chopped pepper and canned chilies. Stir just until moistened. Pour into prepared muffin tin and fill ¾ full.
Bake muffins 15-20 minutes until golden brown. Serve hot with butter or margarine.
If using 9- inch pan adjust baking time to 25-30 minutes.