Preheat and Prep: Heat your oven to 220°C (425°F). Grease a standard 9×5 inch loaf pan or a small oven-safe glass dish with butter or non-stick spray.
Mix Dry Ingredients: In a large bowl, whisk together the flour, baking powder, and salt (and sugar, if using) until well combined.
Combine Wet and Dry: Pour in the milk and the melted butter (or oil). Stir with a spatula or wooden spoon just until the flour is moistened. The batter will be thick, sticky, and shaggy—don't overmix it, or the bread will be tough.
Bake: Spread the dough evenly into the prepared pan. Bake for 15 to 18 minutes, or until the top is golden brown and a toothpick inserted into the center comes out clean.
Serve: Let it cool for just a minute or two in the pan, then slice and serve warm with plenty of butter.
Quick Tips for Success
Don't Overwork It: Stop mixing as soon as you don't see any more dry flour streaks.
The Crust: For a softer, shinier crust, brush the top of the loaf with a little extra melted butter immediately after taking it out of the oven.
Add-ins: Since this is a “whisk and pour” style bread, you can easily stir in a handful of shredded cheddar cheese or some dried herbs like rosemary or garlic powder before adding the wet ingredients.