Preheat oven to 350°F (175°C). Thoroughly grease and flour a Bundt pan, making sure to coat every nook and cranny.
In a medium bowl, whisk together flour, baking soda, salt, cinnamon, nutmeg, and allspice until well combined.
In a separate large bowl, beat together sugar and oil until smooth. Add eggs one at a time, beating well after each addition. Stir in vanilla extract.
Gradually add the dry ingredients to the wet mixture, folding gently until just combined. Do not overmix.
Fold in the chopped apples and nuts (if using), distributing them evenly throughout the batter. For best results, toss the apples in a tablespoon of flour before adding to prevent them from sinking.
Pour the batter into your prepared Bundt pan, smoothing the top with a spatula.
Bake for 60-65 minutes, or until a toothpick inserted in the center comes out clean with a few moist crumbs. The cake should spring back when lightly pressed.
While the cake cools, prepare the glaze. In a small saucepan, bring apple cider to a boil over medium heat. Reduce to about ¼ cup, approximately 10-15 minutes.
Remove from heat and whisk in butter until melted. Gradually add powdered sugar, cinnamon, and salt, whisking until smooth and glossy.
Allow the cake to cool in the pan for 10 minutes, then invert onto a wire rack to cool completely. Place parchment paper under the rack for easy cleanup.
When the cake has cooled, drizzle the warm glaze over the top, allowing it to cascade down the ridges of the Bundt cake. For extra flavor, poke small holes in the cake with a skewer before glazing.