Lighly spray the loaf pan with oil spray then lighly dust with flour. Set it aside.
In a bowl, combine flour, baking powder, baking soda, salt, and ground cinnamon.
Wash and dry the zucchini thoroughly before shredding.
In a mixer bowl, combine eggs, sugar, and apple sauce.
Add the vanilla extract and shredded zucchini.
Mix together until well-combined.
Gradually add the flour mixture while continiuing to mix.
Scrape the sides of the bowl. Add sour cream then mix again to blend well.
Turn the mixer off. Reserve some of the chocolate chips then pour the rest into the bowl. Gently fold the whole thing together.
Preheat the oven to 350°. Pour the batter into the prepared loaf pan. Sprinkle the reserved chocolate chips on top. Bake it in the oven for an hour. After the hour, loosely cover the pan with foil to cook for another 15 minutes.
Cool in the pan for 10-15 minutes before lifting it out of the pan.
Cool completely in a rack or serving board.