Preheat the oven to 350 degrees. Line a 9x5 loaf pan with parchment paper overhanging the sides.
Toast the pecans in a small skillet on low heat for five minutes. Mix it with the rest of the Cinnamon Apple Swirl ingredients and set aside.
In a medium bowl, sift together the flour, salt, and baking soda. Set aside.
In a mixing bowl, whisk together the egg, vanilla, butter, and sugar. Add the buttermilk and dry ingredients, alternating them. Stir until everything is just combined.
Pour half of the batter into the pan. Top with half of the Cinnamon Apple Swirl mixture. Add the rest of the batter, and smooth it over the swirl mixture. Then, add the rest of the Cinnamon Apple Swirl mixture. Then, use a knife to make a swirl going through the loaf.
Bake on the middle oven rack for 50 minutes, or until a toothpick comes out clean. Let it cool in the pan on a rack for ten minutes, and then lift it out of the pan to let it cool completely on the rack.