In a bowl, mix diced apples with brown sugar and cinnamon.
Beat softened butter and sugar until light and fluffy.
Add eggs one at a time, then stir in vanilla and sour cream.
In a separate bowl, whisk flour, baking powder, baking soda, salt, and cinnamon. Fold into the wet mix until just combined.
Pour half the batter into a greased loaf pan, layer with half the apples, repeat. Bake at 350°F (175°C) for 50–60 mins or until a toothpick comes out clean.
Notes
Drizzle with glaze once cooled for added sweetness.
Use Honeycrisp or Granny Smith apples for the best flavor.