Preheat your oven to 350°F (177°C). Grab a 9x5-inch loaf pan, give it a generous spray with nonstick, and set it aside.
In a big bowl, combine your dry ingredients: flour, baking soda, baking powder, cinnamon, and salt. Stir them together until everything is well mixed. Set the whole bowl aside; we'll be back to it shortly.
Grab a medium bowl and gather your wet ingredients: oil, brown sugar, peanut butter, eggs, honey, milk, and a splash of vanilla. Stir until smooth and creamy
Pour your wet mixture into the bowl with the dry ingredients, then use a spatula to fold everything together with a gentle hand.JUST until it all looks combined. Fold in the grated zucchini and some chocolate chips.
Scoop and spread the batter into your prepared pan and bake (55 to 70 minutes). About halfway through, loosely cover the top with foil. You'll know it's ready when a small toothpick poked into the middle comes out mostly clean.
Take the bread out and let it chill in the pan on a wire rack for about an hour before serving. But if you don't mind a slightly warm, gooey taste, go ahead and cut in.