Preheat your oven to 350ºF. Line a 9×5-inch loaf pan with parchment paper and grease it with cooking spray.

In a medium bowl, whisk together the 1 1/2 cups of flour, baking powder, baking soda, cinnamon, and salt.

In a large mixing bowl, beat the granulated sugar and room temperature butter until creamy and fluffy, about one minute.

Incorporate the eggs and vanilla extract into the mixture, mixing until everything is well combined.

Gradually fold in the flour mixture in two parts, alternating with the buttermilk. Remember, do not overmix!

In a different bowl, mix together melted butter, light brown sugar, salt, and cinnamon for the crumble. Add the flour and mix with a fork until crumbly.

Toss diced apples with additional cinnamon and mix one-third into the batter.

Pour half the batter into your prepared pan, layer in another third of the apple mixture, top with the remaining batter, then finish with the last third of apples and the crumble topping.

Slide it into your preheated oven and bake for 60-80 minutes, or until a toothpick comes out clean. If the top gets too dark, lightly cover it with foil.

Let the loaf cool for about 15 minutes in the pan before transferring it to a cooling rack.

Whisk your glaze ingredients together and drizzle it over the cooled loaf for that final touch.