Preheat your oven to 180°C (350°F). Grease a 9x5 inch loaf pan and lightly dust with flour.
In a large mixing bowl, whisk together the flour, baking powder, salt, and cinnamon until evenly combined.
In a separate bowl, cream the softened butter and brown sugar with a whisk or hand mixer until the mixture is light, fluffy, and slightly pale, about 2-3 minutes.
Add eggs one at a time to the butter mixture, beating well after each addition to incorporate air and achieve a smooth, glossy batter.
Stir in the vanilla extract, then fold in the milk gently to keep the batter tender and moist.
Peel, core, and chop the apples into small chunks. Toss them with a teaspoon of lemon juice if desired, then fold them into the batter carefully so chunks stay intact.
Pour the batter into the prepared loaf pan and smooth the top with a spatula. Sprinkle a teaspoon of cinnamon sugar over the surface for extra aroma and crunch.
Bake in the oven for 50 to 60 minutes, until the top is golden brown and a toothpick inserted into the center comes out clean.
If the top browns too quickly, loosely tent the loaf with foil and continue baking until done.
Remove the bread from the oven, let it cool in the pan for 15 minutes, then transfer to a wire rack to cool completely.
Once cooled, slice the bread with a serrated knife to reveal a moist, tender crumb flecked with apple chunks and cinnamon.
Enjoy warm or at room temperature, perhaps with butter or a drizzle of honey for extra comfort.
