Step 1: Preheat your oven to 350°F (175°C). Prepare your bundt pan by spraying it with non-stick baking spray or greasing it lightly with oil and dusting it with flour to ensure the cake doesn’t stick.

Step 2: In a medium mixing bowl, crack the eggs and add both the white sugar and brown sugar. Beat the mixture using a hand mixer or a stand mixer on medium speed for about 4-5 minutes until it becomes light and creamy.

Step 3: Add the vegetable oil and vanilla extract to the sugar-egg mixture, mixing on low speed for about 1-2 minutes until everything is well combined. Afterward, fold in the pumpkin puree and mix for an additional minute to achieve a smooth consistency.

Step 4: In a separate large bowl, combine the sifted all-purpose flour, baking soda, baking powder, salt, and cinnamon. Whisk these dry ingredients together to ensure everything is well incorporated.

Step 5: Gradually add the dry ingredients into the wet ingredients. Mix gently, using a spatula or a mixer on low speed, until just combined. Be careful not to overmix, as this can result in a dense cake. Once the batter is mostly smooth, fold in the diced apples carefully, ensuring they are evenly distributed throughout the batter.

Step 6: Pour the cake batter into the prepared bundt pan, spreading it evenly. Give the pan a few gentle taps on the counter to remove any air bubbles.

Step 7: Place the bundt pan in the preheated oven and bake for 50-60 minutes. The cake is done when a toothpick inserted into the center comes out clean, with only a few moist crumbs attached.

Step 8: Once done, remove the bundt pan from the oven and let the cake cool on a wire rack for about 40 minutes. After cooling, carefully invert the cake onto a serving platter by placing the platter over the bundt pan and flipping it over.

Step 9: Allow the cake to cool completely before slicing it. This will ensure the cake sets properly and holds its shape. Now, all that’s left is to slice, serve, and enjoy!