Preheat oven to 350°F. Spray a loaf pan with nonstick spray or line with parchment paper, letting it hang over the sides for easy removal.
In a medium bowl, combine chopped apples, brown sugar, cinnamon, and ginger. Mix until apples are well coated. Set aside.
In a large mixing bowl, whisk together egg, granulated sugar, vegetable oil, sour cream, and vanilla extract for about 30 seconds until smooth and creamy.
In a separate bowl, whisk together flour, baking soda, and salt.
Add dry ingredients to wet ingredients. Fold gently with a rubber spatula until just combined. Some small lumps are okay - don't overmix.
Reserve about one quarter of the apple mixture for topping. Fold the remaining apples gently into the batter.
Pour batter into prepared loaf pan and spread evenly. Scatter reserved apple chunks over the top. Tap pan on counter a couple times to remove air bubbles.
Bake for 50 minutes, or until a toothpick inserted in the center comes out clean with a few moist crumbs. If top browns too quickly, tent loosely with foil.
Let bread cool in pan for at least 30 minutes to 1 hour before removing. This prevents crumbling.
While bread cools, make the glaze: Sift powdered sugar into a small bowl. Add vanilla and milk. Whisk until completely smooth. Adjust consistency with more milk or powdered sugar as needed.
Once bread is completely cool, drizzle glaze over the top. Let set for 10 minutes before slicing.