1. Preheat oven to 350°F (175°C). Grease a 9×13-inch baking pan.

2. Peel, core, and dice apples. Toss them with 1 tablespoon brown sugar and 1/2 teaspoon cinnamon. Set aside.

3. In a medium bowl, mix flour, baking powder, baking soda, salt, cinnamon, and nutmeg.

4. In a large bowl, cream together butter and sugar until light and fluffy. Add eggs one at a time. Stir in sour cream and vanilla.

5. Gradually mix the dry ingredients into the wet until just combined.

6. To make the streusel, combine flour, brown sugar, and cinnamon in a bowl. Cut in butter until crumbly. Stir in chopped pecans.

7. Spread half the cake batter into the prepared pan. Layer apples evenly over the batter. Spread remaining batter on top.

8. Sprinkle streusel topping evenly across the cake.

9. Bake for 40–45 minutes or until a toothpick inserted comes out clean.

10. Cool on a wire rack. Drizzle with caramel before serving if desired.