Preheat oven to 350°. Spray or use parchment paper an 8 x 5 loaf pan.
In a small bowl, whisk brown sugar and cinnamon for topping.
In a large bowl, whisk eggs and granulated sugar. Add melted butter and vanilla and thoroughly combine.
In a medium bowl, sift or mix together dry ingredients. Add to large bowl and stir until just combined. Batter will be thick.
Fold in apples.
Add half the batter to the loaf pan. Sprinkle ¾ of the brown sugar mixture. Spread the remaining batter and top with remaining brown sugar.
Bake for 45 minutes or until lightly golden on top and inserted toothpick comes out clean with a few moist crumbs. Tent with foil for last 15 minutes if the top gets too brown.
Cool completely before slicing.