Preheat your oven to 350°F (175°C) and spray a 9 x 5 inch bread pan with non-stick spray. Meanwhile, wrap the shredded zucchini in a paper towel and gently squeeze to remove some of its excess liquid. You don’t need to dry it out completely—just release about a tablespoon of liquid.

In a large bowl, combine the flour, baking powder, baking soda, and table salt. Mix thoroughly to evenly distribute the leaveners and salt throughout the flour.

In a separate small bowl, combine the milk and vinegar. Allow it to sit for a moment so the milk curdles slightly, creating a homemade buttermilk. Then, whisk in the melted butter and the egg until the mixture is smooth.

Add the wet milk mixture to the dry flour mixture. Gently fold them together, being careful not to overmix.

Fold the shredded zucchini, grated cheddar cheese, and chopped green onions into the batter. Mix just until everything is evenly distributed.

Pour the batter into the prepared pan, bake at 350°F for about one hour, or until a toothpick inserted in the center comes out clean. Let the bread cool in the pan for 10 minutes before transferring to a wire rack to finish cooling.