Prep and preheat
Preheat your oven to 350°F (175°C). Grease a standard 9×5-inch loaf pan and line the base with parchment for easy removal.
Make the cinnamon-sugar swirl
In a small bowl, mix together the brown sugar and 1 teaspoon cinnamon. Set aside.
Cream the butter and sugars
In a medium bowl, beat the softened butter with white sugar until light and fluffy, about 2–3 minutes.
Add eggs and vanilla
Beat in eggs one at a time, then mix in vanilla extract until well combined.
Combine dry ingredients
In a separate bowl, whisk together flour, baking powder, and salt.
Build the batter
Alternate adding dry ingredients and a portion of the batter to the wet mixture, starting and ending with dry ingredients, just until mixed.
Prepare the apple filling and swirl
Toss the diced apples with 2 tablespoons white sugar and 1 teaspoon cinnamon. Set aside.
In a small bowl, mix the remaining 1/3 cup light brown sugar with 1 teaspoon cinnamon (and nutmeg if using).
Layer and swirl
Pour half of the batter into the prepared loaf pan and spread evenly.
Sprinkle half of the apple mixture over the batter.
Dot with half of the cinnamon-sugar swirl, then add the remaining batter to cover.
Spoon the rest of the apple mixture on top. Use a knife to gently swirl some of the cinnamon-sugar mixture into the batter, creating ribboned swirls.
Bake
Bake for 55–65 minutes, or until a toothpick inserted into the center comes out clean with a few moist crumbs.
If the top browns too quickly, tent with foil during the last 15 minutes.
Cool and glaze (optional)
Let the loaf cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
If you’re glazing, whisk powdered sugar with milk or apple cider and a touch of vanilla, drizzle over cooled loaf.
Serving suggestions and presentation
Slice warm with a pat of butter or a scoop of vanilla ice cream.
Add a cinnamon-dusted finishing touch with a light dusting of extra cinnamon on top.
Pair with a hot chai, cinnamon tea, or a latte for a perfect autumnal treat.
