Prepare the oven and pan: Preheat the oven to 350°F. Generously coat a 10-cup Bundt pan with nonstick cooking spray, making sure to cover all the crevices.
Mix the wet ingredients: In a large mixing bowl, beat the eggs, sugar, vanilla extract, and olive oil until the mixture is light and well combined.
Combine the dry ingredients: In a separate bowl, whisk together the flour, baking powder, and spices until evenly combined.
Make the cake batter: Gradually add the dry ingredients to the wet ingredients, mixing until the batter is smooth and well blended. Avoid overmixing.
Add the apples and walnuts: Gently fold in the chopped apples and walnuts until evenly distributed throughout the batter.
Bake the cake: Pour the batter into the prepared Bundt pan and spread it evenly. Bake for about 45 - 50 minutes, or until a toothpick inserted into the center comes out clean.
Cool and remove the cake: Let the cake cool in the pan for 20 minutes. Carefully run a knife around the edges to loosen it, then invert the cake onto a serving plate. Allow it to cool completely before glazing.
Prepare the cinnamon glaze: In a small bowl, whisk together 2 cups of powdered sugar, 2 tablespoons of milk, and ½ teaspoon of cinnamon until smooth. If the glaze is too thick, add a little more milk, a few drops at a time
Glaze and serve: Drizzle the cinnamon glaze over the completely cooled apple Bundt cake. Alternatively, keep it simple with a light dusting of powdered sugar. Slice and serve.