Preheat your oven to 350°F (175°C) and prepare an 8 x 5 inch loaf pan by greasing it with butter or oil and dusting it with flour, or line it with parchment paper.

In a small bowl, combine 1/3 cup of brown sugar with 1 teaspoon of ground cinnamon, stirring well to create an aromatic mixture. Set aside.

In a large mixing bowl, whisk together 2 large room-temperature eggs and 1/2 cup of granulated sugar until well-blended and slightly fluffy.

Stir in 1/2 cup of melted butter and 1 teaspoon of vanilla extract to the egg mixture, blending until smooth and combined.

Gradually add 1 1/2 cups of all-purpose flour, 1 teaspoon of baking powder, 1/2 teaspoon of baking soda, and 1/4 teaspoon of salt to the wet ingredients. Mix gently until just combined.

Gently fold in 2 cups of chopped apples into the batter until evenly distributed.

Pour half of the apple bread batter into the prepared loaf pan, spreading it smoothly. Sprinkle three-quarters of the brown sugar and cinnamon mixture over the batter.

Spoon the remaining batter on top and gently spread it. Sprinkle the remaining brown sugar mixture on top and use a knife to swirl it lightly into the batter.

Place the loaf pan in the preheated oven and bake for 35-45 minutes, or until a toothpick comes out clean.

Once baked, let it cool in the pan for about 10 minutes before transferring to a wire rack to cool completely.