1. Preheat oven to 400 and grease a 10" cast iron skillet with oil. Alternatively you can grease a 9" square baking pan. Set aside.
2. In a large bowl, combine muffin mix, eggs, buttermilk, sour cream, jalapenos and red pepper and mix.
3. Mix in butter and pour batter into prepared pan.
4. Bake for 25-30 minutes or until toothpick inserted in the center comes out clean. Cool slightly before serving warm.