• Preheat oven to 350°F. Spray a 9x5-inch loaf pan with a nonstick spray. Set aside.
• In a small bowl, mix ⅓ cup brown sugar, 1 teaspoon cinnamon, and the peeled and diced apples together. Set aside.
  ⅔ cup brown sugar, 2 teaspoons ground cinnamon, 2 apples
  
• In another bowl, using a hand or stand mixer, beat the granulated sugar and butter until smooth and creamy. Add in the egg and applesauce; mix until combined. Mix in the vanilla. Set aside.
  ½ cup granulated sugar, ½ cup unsalted butter, 1 large egg, ¼ cup unsweetened applesauce, 1½ teaspoons pure vanilla extract
  
• In a medium bowl, whisk the flour, baking powder, and salt. Add the dry ingredients into the wet ingredients. Begin to mix the two and gradually add milk; continue mixing until smooth.
  1½ cups all-purpose flour, 1¾ teaspoons baking powder, ¼ teaspoon kosher salt, ½ cup milk
  
• Pour half of the batter into the prepared loaf pan. Sprinkle half of the remaining brown sugar and half of the remaining cinnamon over the top. Layer half of the cinnamon apples on top. Pour the remaining batter over the apple layer. Sprinkle with the remaining cinnamon apples, the remaining brown sugar and cinnamon. Top with coffee cake crumble topping (see below) if using.
  
• Bake for 45-50 minutes, or until a toothpick inserted into the middle comes out clean. Cool for 10 minutes and then remove from pan and cool on a rack.

For the Coffee Cake Crumble Topping

• Prepare the crumble topping by mixing of the crumble ingredients together with a fork. Once the topping crumbled, sprinkle it evenly over the batter BEFORE baking.
  4 tablespoons unsalted butter, ½ cup all-purpose flour, ½ cup brown sugar, 1 teaspoon ground cinnamon, ½ teaspoon kosher salt

For the Glaze

• Prepare the glaze by mixing the powdered sugar with 2 tbsp of milk, slowly add more milk and keep mixing until the desired consistency has been reached. Drizzle over the cooled bread AFTER baking.
  ½ cup powdered sugar, 2-4 tablespoons milk