Combine the sugar, flour, cinnamon, salt, and pecans in a small mixing bowl and stir to combine. Add the butter and use your fingers to cut the butter into the dry ingredients until it comes together and forms crumbles. Refrigerate while you work on the cake.

Preheat the oven to 350 degrees. Spray a 9-inch springform pan with cooking spray and set aside.

Combine the sugar and butter in a large mixing bowl and beat with an electric mixer set to medium until light and fluffy, stopping to scrape the sides of the bowl as necessary. Add the eggs and beat until smooth.

Add the cinnamon, vanilla, baking powder, baking soda, and salt and beat to combine. With mixer on low, beat in half the flour followed by half of the sour cream. Stop mixer and scrape down the bowl, then beat in the remanning flour and remaining sour cream (batter will be thick).

Use a rubber spatula to fold in the chopped apples.

Scrape half of the batter into the prepared pan and sprinkle with about one-third of the topping. Gently spread the remaining cake over the topping and sprinkle the remaining topping over the top. Press the topping down lightly.

Bake for 55 to 60 minutes, until a toothpick inserted into the center of the cake comes out clean. (If the top of the cake starts to get too brown you can tent some foil over it toward the end of baking time.) Cool to room temperature on a wire rack, then dust with powdered sugar and serve.

Cake is best served the day it’s made but uneaten cake can be stored, covered, in the fridge for up to 2 days.