Heat oven to 425 degrees. Lightly butter an 8-inch square pan. Set aside.
In a medium bowl, combine flour, cornmeal, baking powder, salt, and pepper.
In another bowl, whisk together buttermilk, jalapenos, egg, sugar, and 2 tablespoons melted butter. Add to dry ingredients, and stir until just combined.
Pour batter into prepared pan, and bake until golden brown, about 20 minutes. Remove from oven, and cool for 10 minutes. Invert onto a wire rack to cool completely.
Recipe courtesy Martha Stewart