Preheat the oven to 450 degrees F. Combine the cornmeal, flour, baking powder, salt and dried herbs in a large bowl and stir together. Combine the buttermilk, milk and egg in a small bowl and stir together with a fork. Add the baking soda and stir. Pour the milk mixture into the dry ingredients and stir with a fork until just combined. Do not overmix.
In a small bowl, melt 1/4 cup shortening in the microwave in 30-second intervals. Add the melted shortening to the batter, stirring constantly, until combined. Melt the remaining 2 tablespoons shortening in a 9-inch cast-iron skillet over high heat. Pour the batter into the hot skillet and spread to even out the surface. Cook 1 minute on the stovetop, then transfer to the oven and bake 20 to 25 minutes, until the cornbread is golden brown with crispy edges. Let cool 15 minutes in the skillet, then turn out onto a rack to cool completely.