Preheat the oven to 350 degrees. Prepare a 9x5-inch loaf pan by spraying it with non-stick cooking spray. You can also line it with foil or parchment paper for easy removal and slicing, and spray it with non-stick cooking spray.

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

In a separate bowl, combine and whisk 1 & 1/2 cups flour and 1 & 3/4 teaspoons baking powder. Set aside.

In another medium-sized bowl, use an electric mixer to beat 2/3 cup granulated sugar and 1/2 cup softened butter until smooth and creamy.

Beat in the eggs one at a time until blended into the butter/sugar mixture. Add 1 & 1/2 teaspoons vanilla extract and mix in.

Add the flour mixture to the creamed butter mixture and mix until blended.

Mix in 1/2 cup milk until smooth.

Toss chopped apples with 2 tablespoons granulated sugar and 1 teaspoon cinnamon in a bowl.

Pour half of the apple bread batter into the prepared loaf pan and spread it out. Top with half of the chopped apple mixture.

Sprinkle 1/2 of the brown sugar/cinnamon mixture on top.

Pour the remaining apple bread batter into the loaf pan and spread it out. Top with the remaining chopped apple mixture.

Sprinkle the remaining brown sugar/cinnamon mixture on top.

Use a knife to swirl through the mixture a few times.

Bake in the preheated oven until a toothpick inserted into the center of the loaf comes out clean, approximately 60 minutes.

Mix 1/2 cup powdered sugar and 1 to 3 tablespoons milk or cream until well combined.

If needed, place the mixture in the microwave for 10 seconds to make it pourable.

Let the loaf rest in the pan for about 15 minutes before removing it to cool completely on a cooling rack. Drizzle with glaze, and for extra glaze, you can make a double batch.