Preheat your oven to 325 degrees F. Prep your pan goop by mixing the flour and the softened butter in a small bowl until combined. With a pastry brush, brush the sides and all cracks and crevices of the pan with the goop. Set aside.
In a medium size mixing bowl, whisk the flour, cinnamon, nutmeg, salt, and baking powder. Set aside.
In a stand size mixer fitted with the whisk attachment, whisk the sugar, brown sugar and oil on medium speed for 2 minutes.
Add the eggs to the sugar mixture and continue to mix on medium speed for 2 minutes. Add the vanilla and the applesauce mix on low just until incorporated.
With the mixer on low speed, add ⅓ of the flour mixture, then add half of the apple cider. Mix until almost combined, then add another ⅓ of the flour mixture and the rest of the apple cider, finally add the rest of the flour mixture. Mix until no streaks of flour remain.
Pour the batter into the prepped bundt pan and bake for 50-54 minutes. To test to see if the cake is done, use a toothpick and insert it the thickest part of the cake and it should come out with a few or no crumbs.
Let the cake completely cool in the bundt pan before turning it over onto a large plate, cake board, or cooling wrack.
Right before you serve it, use a sifter and sift the powder sugar on top, and serve right away.