Preheat and Prepare:

Preheat your oven to 350°F (175°C). Grease an 8.5x4.5x2.5-inch loaf pan with non-stick spray or butter.

Prepare the Brown Sugar Mixture:

In a small bowl, mix together 1/3 cup brown sugar and 1 teaspoon ground cinnamon. Set aside.

Cream the Butter and Sugar:

In a large mixing bowl, cream together the softened butter and 2/3 cup granulated sugar using an electric mixer until the mixture is light and fluffy. Beat in the eggs, one at a time, then add the vanilla extract.

Combine Dry Ingredients:

In a separate bowl, whisk together the flour and baking powder. Gradually add the dry mixture to the creamed mixture, alternating with the milk, and mix until smooth.

Assemble the Bread:

Pour half of the batter into the prepared loaf pan, spreading it evenly. In a separate bowl, mix together the apple filling ingredients (apples, cinnamon, and sugar). Layer half of the apple mixture over the batter. Add the remaining batter on top, followed by the rest of the apple mixture, pressing the apples gently into the batter.

Add the Topping:

Sprinkle the reserved brown sugar and cinnamon mixture over the top of the bread.

Bake the Bread:

Bake in the preheated oven for about 60 minutes, or until a toothpick inserted into the center comes out clean. Allow the bread to cool in the pan for about 30 minutes.

Prepare the Glaze:

In a small bowl, mix together the powdered sugar and milk until smooth. Adjust the milk as needed to reach your desired consistency.

Glaze the Bread:

Drizzle the glaze over the cooled bread. Let it set before slicing.

Serve and Enjoy:

Slice the bread and serve. Enjoy the warm flavors of apple and cinnamon with a sweet glaze on top!