Preheat your oven to 350°F (175°C). Grease a 9x5-inch loaf pan with butter or non-stick spray.
Mix the dry ingredients: In a large bowl, whisk together the flour, baking powder, baking soda, salt, garlic powder, oregano, and thyme.
Add the cheese: Stir in the cheddar, mozzarella, and Parmesan, ensuring the cheese is evenly coated with the dry ingredients.
In a separate bowl, whisk together the buttermilk, melted (cooled) butter, and eggs until smooth.
Combine wet and dry ingredients: Pour the wet mixture into the dry ingredients and gently mix until just combined. Avoid overmixing to keep the bread light.
Transfer & bake: Pour the batter into the greased loaf pan, spread it evenly, and bake for 45-50 minutes until golden brown. A toothpick inserted in the center should come out clean.
Let the bread cool in the pan for 10 minutes, then transfer to a wire rack.