Preheat oven to 375°F. Grease a muffin pan with nonstick cooking spray or line with paper liners.
In a large bowl, combine the flour, cornmeal, sugar, baking powder, baking soda, and salt.
In a separate bowl whisk together the buttermilk, butter, vegetable oil, egg and egg yolk.
Add the wet ingredients to the dry ingredients and gently stir together. Fold in the corn kernels. Do not overmix, batter should be somewhat lumpy.
Pour batter into the prepared pan, filling each muffin cup 2/3 way full. Bake until edges are golden, 12-15 minutes. Serve warm or at room temperature.
Store muffins in an airtight container at room temperature for up to several days.
Calories: 194kcal, Carbohydrates: 26g, Protein: 4g, Fat: 9g, Saturated Fat: 5g, Cholesterol: 40mg, Sodium: 174mg, Potassium: 189mg, Fiber: 2g, Sugar: 6g, Vitamin A: 168IU, Vitamin C: 1mg, Calcium: 65mg, Iron: 1mg