Preheat oven to 350 degrees F. Grease and flour a 9×5×3-inch loaf pan and set aside.

In a medium bowl, whisk together flours, sugar, salt, baking powder, baking soda, cinnamon and nutmeg.

In a small bowl, whisk together buttermilk, eggs, melted butter and vanilla extract. Mix the wet ingredients into the dry ingredients.

Add the grated apples, chopped apples, flax seeds and half of the chopped walnuts. Fold to incorporate thoroughly.

Spoon batter into prepared pan and top with granulated sugar, cinnamon and the rest of the walnuts.

Bake for 40 to 50 minutes or until a skewer inserted in the center of the loaf comes out clean. Let cool in the pan for 15 minutes then invert onto a cooling rack to cool before wrapping.