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

In a large bowl, combine the flour, baking powder, baking soda, and salt. Mix thoroughly.

In a small bowl, combine milk and vinegar. Let it sit to curdle slightly. Whisk in melted butter and egg until smooth.

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

Fold in the zucchini, cheddar cheese, and green onions. Mix until evenly distributed.

Pour batter into the prepared pan, bake at 350°F (175°C) for about an hour. Cool in the pan for 10 minutes before transferring to a wire rack to cool completely.