Preheat the oven to 350 degrees F (175 degrees C). Grease a 9x13 inch baking dish.
Make topping: Mix brown sugar, pecans, cinnamon, and nutmeg together in a small bowl until well combined. Set aside.
Make cake: Sift flour, baking powder, baking soda, and salt into a medium bowl. Set aside.
Beat sugar and butter together in a large bowl with an electric mixer until light and fluffy. Add eggs one at a time, mixing well after each addition. Add apple butter, bran cereal, and vanilla; stir until incorporated. Add flour mixture alternately with sour cream, mixing well after each addition.
Pour 1/2 of the batter into the prepared baking dish; sprinkle with 1/2 of the topping. Cover with remaining batter and sprinkle with remaining topping.
Bake in the preheated oven until a toothpick inserted into the center of cake comes out clean, about 40 minutes.
Apple Butter Spice Cake · Dinner Match Lab | Dinner Match Lab