Heat the Oven: Position a rack in the center of the oven, and heat the oven to 350 ℉ (176 ℃). Butter and flour a 10-inch round cake pan. Set aside.
Sift the Dry Ingredients: In the bowl of a stand mixer fitted with a paddle attachment, sift together the flours, baking soda, and spices.
Add the Sugar and Butter: Add the sugars and butter to the flour mixture. Beat on medium speed, until the butter is fully incorporated into the dry ingredients, approximately 1-2 minutes. Stop the mixture a couple of times, scraping down the sides of the bowl with a spatula, to ensure the butter is mixed in. Add the Eggs: Add the eggs to the bowl, one at a time, mixing after each addition to ensure they are fully combined (approximately 20 seconds each).
Add the Molasses, Sour Cream & Vanilla: In a small bowl, whisk together the molasses, sour cream, and vanilla. Add to the mixing bowl and mix on low until it is fully combined, approximately 1 minute. Scrape down the sides of the bowl to ensure it is fully combined. Then, turn the mixer on medium-high and beat the batter for approximately 2-3 minutes, or until the batter is light and fluffy. Add the Apples: Remove the bowl off of the stand mixer. Using a rubber spatula, fold the apples and pecans in (if you're using raisins, you can add them at this stage). The batter will be stiff and thick.
Pour in Pan and Bake: Scrape the batter into the prepared pan. Bake the cake for approximately 1 hour and 20 minutes, or until the cake is firm to the touch and the top is a golden brown. Allow the cake to cool completely on a wire rack.
Serve: Once cooled to room temperature, invert the cake onto a serving platter, lifting it gently away from the pan, and then invert the cake again so it is right side up. Dust the cake with confectioner's sugar before serving. The cake can be stored in an airtight container at room temperature for up to three days. Or, it can be well wrapped in plastic wrap and frozen for up to 2 weeks. To enjoy, simply thaw overnight at room temperature.