Preheat oven to 350 degrees. Grease a 9" round springform pan with cooking spray. Melt the butter in a small bowl and set aside to cool.

In a small bowl, whisk together the flour, baking powder and salt.

In a large bowl, whisk the eggs and sugar vigorously until frothy, about 1 minute, then whisk in the bourbon and vanilla.

Whisk half of the flour into the wet ingredients just until incorporated, then whisk in half of the butter until just combined. Whisk in the remaining half of the flour, then the remaining half of the butter. Fold in the apples until well coated with the batter.

Pour the batter into the prepared pan and spread evenly and bake on the middle rack of the oven for 40 minutes or until golden brown and a toothpick inserted into the center comes out clean.

Cool 10 minutes on a wire rack, then remove from pan, using a knife to loosen the cake from the sides of the pan if necessary. Serve and enjoy!