In a large bowl, whisk together the flour, cocoa powder, baking soda, baking powder and salt. Set aside.
1 1/2 Cups Flour, 1/2 Cup Dutch Process Cocoa Powder, 1/2 teaspoon Baking Soda, 1 teaspoon Baking Powder, 1/2 teaspoon Salt
In a medium bowl, whisk together the oil, sour cream, eggs, vanilla, and white sugar.
1/2 Cup Vegetable Oil, 1/4 Cup Sour Cream, 2 Large Eggs, 1 teaspoon Vanilla Extract, 1 Cup Sugar
Stir the zucchini in and then pour the wet ingredients into the dry ingredients along with 3/4 cup of mini chocolate chips (Reserve a few of the chocolate chips to sprinkle on top of the muffins) and using a rubber spatula, fold until just combined.
2 Cups Zucchini, 1 Cup Mini Semi Sweet Chocolate Chips
Divide batter evenly into muffin tins, filling all the way full. Place a few reserved chocolate chips on top of each muffin.
Preheat oven to 350° F. Line every other hole in 2 12 cup muffin tins with cupcake liners. See note. Set the batter filled cups aside to rest while the oven heats. See post under "tips"
Bake for 15 minutes at 350° . Touch the tops and if they don't sink in they are done (or until toothpick comes out clean or with just a few moist crumbs attached). Turn off the oven and open the door, gently sliding the rack out a little. Let them sit for a good 2-3 minutes then remove to cool on the counter on a wire rack.
Notes
You do not have to do every other hole but it helps the air to circulate and give a taller dome to the muffins.
Keep in an airtight container at room temperature for 3 days or in the freezer for up to 1 month.
You can use 1/4 cup brown sugar and 3/4 cup white sugar if you're looking for a little more chew to the muffin tops