Preheat your oven to 350°F (175°C).
Prepare two 9x5-inch loaf pans: spray one with baking spray for layering, and leave the other one ungreased for baking.
In a small bowl, mix the brown sugar and cinnamon, then set aside.
In a stand mixer with a paddle attachment, cream the butter and sugar together until light and fluffy, about 3 minutes. If you don’t have a stand mixer, use a large bowl and an electric mixer.
Add the eggs one at a time, mixing well after each and scraping the sides and bottom of the bowl.
Add the vanilla extract and mix for 30 seconds.
In a separate medium bowl, combine the flour, salt, and baking powder. Slowly add this to the butter mixture, mixing until just combined (don't overmix).
Stir the milk into the batter until smooth.
Pour half of the batter into the ungreased loaf pan.
Layer half of the apples evenly over the batter.
Sprinkle half of the brown sugar-cinnamon mixture on top of the apples.
Drizzle 2 tablespoons of maple syrup over the apples and sugar mixture.
Add the remaining batter on top, followed by the rest of the apples, brown sugar-cinnamon mix, and 2 more tablespoons of maple syrup.
Use an ice cream scoop or large spoon to transfer the batter to the greased loaf pan. This helps distribute the caramelized goodness throughout the bread.
Bake for 50–60 minutes, or until a toothpick inserted into the center comes out clean.
Let the loaf rest for 5 minutes, then run a knife around the edges to loosen it.
Flip the loaf out onto a wire rack to cool. Place the rack on a baking sheet to catch any glaze.
Let the bread cool for 15 minutes before adding the glaze.