Preheat your oven to 350 degrees F. Line one 9x5 inch loaf pan with parchment paper, or grease well with nonstick spray.
If you plan to add nuts to your bread, toast them now. Spread about ¾ cup chopped nuts on a dry baking sheet. Toast at 350 for about 5 minutes. Stir the nuts and continue baking in 2 minute intervals, stirring every time, until the nuts are browned and very fragrant.** Set aside to cool.
Mix the dry ingredients. In a medium bowl combine the dry ingredients: 2 cups all purpose flour (spooned and leveled), 1 cup granulated sugar, 1 teaspoon baking soda, 1 teaspoon baking powder, 1 teaspoon kosher salt, 1 and ½ teaspoons cinnamon, ¾ teaspoon nutmeg, and ¼ teaspoon cardamom. Whisk together and set aside.
Mix the wet ingredients. Add ½ cup butter (1 stick) to a large microwave safe bowl. Melt the butter in the microwave.
Add ¼ cup oil, ¾ cup brown sugar*, ¼ cup sour cream, 2 eggs, and 2 teaspoons vanilla. Whisk together until combined.
Shred the zucchini. Shred your zucchini using the side of your box grater with the largest holes. (Don't chop off the knobby end of your zucchini; use it as a handle!) You can also use the grating tool on a food processor to shred your zucchini. You need 12 ounces of zucchini. If you don't have a scale, measure out 2 cups, making sure to pack it in so you get the full amount. Usually this is about 2 smallish-medium zucchini.***
Blot/ Squeeze the zucchini. Once your zucchini is grated, take the time to blot it on a paper towel, or squeeze it out. I like to lay a few paper towels on the counter, spread out the zucchini, then top with another layer of paper towels and press it down until both paper towels are soaked. Blotting your zucchini will keep your bread from being gummy. If you skip this step, you are still going to get great zucchini bread. I prefer the texture when the zucchini is blotted or squeezed.
Add the zucchini to the bowl of dry ingredients and stir together. Add the dry ingredients to the wet ingredients and mix only until just combined.
If you plan to add (1 cup) chocolate chips*** or (¾ cup) nuts, add them to the batter before the flour is even all the way mixed in, see photos. Then stir together with a spatula with as few strokes as possible. Over mixing the batter will result in tough bread.
Pour the batter into the prepared pan. Top your loaf with 1 tablespoon raw or granulated sugar, or a scatter of chocolate chips (or both! But use sparingly, if you add too much it will weigh down your loaf so that it doesn't rise well.)
Bake the bread in the center of the oven at 350 for about 60 minutes. The bread is done when a toothpick or skewer inserted into the center comes out with no batter on it. You may need to bake the bread for up to 70 or even 80 minutes, so prepare to be patient. Do not take it out of the oven until a toothpick comes out clean. (Be sure that you're not seeing chocolate if you used chocolate chips) Cover your bread with foil as it finishes baking if it is getting over browned.
Let your bread cool in the pan set on a wire rack for 15 minutes. At this point, if you used parchment paper, lift your bread out of the pan and let finish cooling on a wire rack. If you didn't use parchment paper, let cool in the pan for 30 minutes. Then flip the bread into your hand or a plate, then transfer back to the cooling rack. Let finish cooling on it's side for extra crispy edges.
Store zucchini bread in a sealed container on the counter for up to 5 days.
Freezer instructions: Make sure that your bread is completely cool, then wrap the entire loaf in plastic. Stick it in ziplock bag and store in the freezer for up to 3 months. Or to stash individual slices, wrap each cooled slice in plastic wrap, and store them all in a large ziplock. Let thaw (still wrapped) at room temperature on the counter. If you are in a hurry you can try heating it up in the microwave at a lower power level, or using the defrost button. Once thaw, we love to toast individual slices of zucchini bread to get them nice and toasty on the edges. And then slather in butter of course.