For the apple slices:

1. In a medium bowl, toss the apple slices with the brandy, cinnamon, and vanilla. Store in the refrigerator until ready to use.

For the brown butter crumb topping:

1. In a small saucepan, melt the butter down and let simmer over medium heat until it has browned and is bubbling. Be careful not to burn it.
2. In a bowl, whisk flour, sugars and baking soda. Add the brown butter and mix until large crumbs form. If the mixture looks to moist, add more flour one teaspoon at a time.

For the sour cream cake:

1. Preheat oven to 350 degrees F. Grease a bundt pan and place the brown butter crumbs at the bottom of the bundt pan. Set aside.
2. In the bowl of your mix master beat together butter, sugar, and vanilla until whipped. Add one egg in at a time, beating on low speed between each installment. Scrape the sides of the bowl.
3. In a separate bowl, whisk flour, baking powder, baking soda and salt together. Set aside.
4. In another separate but small bowl, whisk sour cream and milk together well.
5. Alternate between the flour and the sour cream mixture, adding each to the beaten butter and sugar batter. Mix well between each addition, making sure there are no clumps. The batter should be smooth and airy. Fold ½ cup of the brandied apples, chopped, into the cake batter.
6. Pour the batter into the prepared bundt pan then top it off with the remaining apple slices. Bake for 35-40 minutes or until the cake tester comes out clean.
7. Transfer to a wire rack and let the cake cool before transferring to a cake plate. Dust with confectioner's sugar before serving.