Preheat oven to 450°F. Combine buttermilk, canola oil, sugar, salt, and 2 eggs in a large bowl, stirring with a whisk. Sprinkle baking powder over batter, whisk until blended. Fold in yellow cornmeal, flour, and chopped jalapeno pepper. Spoon batter into a 10 inch cast iron skillet coated with nonstick spray. Bake for 20 minutes or until golden brown.