Preheat the Oven and Prepare the Pan: Preheat the oven to 350°F (175°C). Coat a 9 × 5-inch loaf pan with nonstick cooking spray to prevent the bread from sticking.
Combine the Dry Ingredients: In a large mixing bowl, whisk together the all-purpose flour, sugar, baking powder, baking soda, and salt until evenly distributed.
Mix the Wet Ingredients: In a separate bowl, whisk the buttermilk and large egg until thoroughly combined. Add the melted, slightly cooled butter and whisk again until the mixture is smooth and uniform.
Make the Batter: Pour the buttermilk mixture into the bowl of dry ingredients. Stir gently until the ingredients are just combined. Avoid overmixing, as this can affect the tenderness of the finished bread.
Fold in the Cheese, Zucchini, and Chives: Add the shredded extra-sharp cheddar cheese, squeezed and measured zucchini, and chopped fresh chives. Stir until these ingredients are evenly distributed throughout the batter.
Transfer the Batter to the Pan: Spoon the prepared batter into the greased loaf pan. Spread it evenly so the batter fills the pan uniformly.
Bake the Bread: Place the loaf pan in the preheated oven and bake for approximately 1 hour. The bread is ready when a toothpick inserted into the center comes out clean.
Cool in the Pan: Remove the baked loaf from the oven and let it rest in the pan for at least 10 minutes. This allows the bread to settle and makes it easier to remove.
Remove and Finish Cooling: Carefully invert the loaf pan over a wire cooling rack to release the bread. Allow the loaf to cool on the rack for an additional 5 minutes before slicing and serving.
