Whisk together the dry ingredients in a medium mixing bowl or bowl of a standmixer.
Whisk other the buttermilk, canola oil and egg in small bowl or right in the measuring cup. Pour into dry mixture and mix to until a thick batter forms.
Scrape into the prepared pan and bake 20 minutes or until a thin knife inserted in the middle of the pan come out clean or with just one or two dried crumbs.
Cool completely on a wire rack.
Notes
You can double this recipe and cook it in a 9x13 inch pan. It will be slightly thicker but will work just as well.