Preheat the oven to 350 degrees F (175 degrees C). Using a non-stick spray, coat the inside of the bundt cake pan. 

Combine flour, cinnamon, baking soda, and salt together in a bowl. 

Beat brown sugar and butter with an electric mixer in a large bowl until fluffy. Mix in egg, vanilla extract, and Greek yogurt until well incorporated. Slowly mix in the flour mixture, then fold in the apples. Pour batter into the prepared bundt pan. 

Bake in the preheated oven for 40-50 minutes. Remove from the oven and cool on a wire rack. 

Once cooled, top with powdered sugar if desired.