Preheat the oven to 325F. Grease a bundt cake pan well and set aside.
In a large bowl, whisk together the granulated sugar, brown sugar and vegetable oil.
3/4 cup (150g) granulated sugar, 3/4 cup (150g) lightly packed brown sugar, 1/2 cup vegetable oil*
Whisk in the eggs, and vanilla extract.
3 large eggs, 1 Tbsp vanilla extract
In a separate bowl, toss together the flour, apple pie spice, baking soda, and salt.
3 cups (375g) all-purpose flour, 2 tsp apple pie spice, 1 tsp baking soda, 1/2 tsp salt
Add the flour mixture to the wet ingredients and mix until almost combined. The batter will be thick.
Fold in the chopped apples until just combined. Spoon the batter into the prepared cake pan.
3 medium apples
Bake for 45-55 minutes or until a toothpick inserted into the center comes out clean. Cool in the pan for 10 minutes before inverting the cake onto a cooling rack.
Once the cake is completely cooled. Whisk together the powdered sugar, maple extract, and 1 tablespoon of milk/water at a time until you reach a thick but pourable consistency. Slowly pour over the cooled cake.
1 & 1/2 cups (190g) powdered sugar, 1/2 tsp maple extract**, 2 to 3 Tbsp milk or water
Notes
Leftovers can be stored tightly covered at room temperature for up to 3 days or in the fridge for up to 5 days.*If the batter seems a bit dry, add another 1/4 cup of oil and that should help.**If you don't have or can't find maple extract, you can use maple syrup instead of milk or water, but the flavor won't be as pronounced.