Preheat oven to 350°F
Spray your bundt pan by liberally with nonstick baking spray and set aside.
Combine melted butter, brown sugar, corn syrup and salt into a medium bowl and whisk until the brown sugar is slightly dissolved.
Add in pecans and stir until combined.
Pour your topping mixture into the bottom of your prepped bundt pan and set aside.
Combine cake mix, eggs, vegetable oil, water and sour cream in a large bowl and mix according to package directions. P
Peel, core and dice your apples into very small pieces
Add your apple to the batter and fold in
Pour batter into prepared pan and on top of the pecan topping. Be sure to spread into an even layer
Bake in a 350° oven for 40-45 minutes or until a tooth pick inserted into the center of the cake comes out clean.
Remove from oven and set aside to cool in pan for about 10 minutes.
After 10 minutes run a knife around the edges of the cake. Then invert your Pecan Upside Down Bundt Cake onto a cake plate and cool completely.
Enjoy!