In a large mixing bowl, add the all-purpose flour and create a small well in the center. Add the sugar, salt, and dry yeast into the well.
Gradually pour the ice-cold water into the center while mixing with a wooden spoon or your hands until a shaggy dough comes together.
Transfer the dough to a clean surface. Knead vigorously by hand for about 10 minutes (or use a stand mixer fitted with a dough hook) until the dough becomes completely smooth, shiny, and elastic.
Divide the dough into 2 equal portions for medium loaves, or cut into smaller pieces to shape into traditional individual rolls (pãezinhos).
Place the shaped dough onto a greased or parchment-lined baking tray. Cover gently with a clean kitchen cloth and let it rise in a warm spot for about 40 minutes.
Using a very sharp knife or a razor blade, make one quick, shallow lengthwise cut on top of each loaf. Mist the top of the dough lightly with a water spray bottle.
Preheat your oven to 250°C (480°F). Place an empty, oven-safe baking tray at the very bottom of the oven and fill it with hot water to create a steam-filled environment.
Place the bread tray in the oven. Bake at 250°C (480°F) for 10 minutes, then reduce the temperature to 200°C (390°F) and bake for another 10 minutes.
Carefully remove the water tray from the bottom of the oven and continue baking the bread for 30 more minutes. (Optional: turn on the broiler during the last 10 minutes for an extra deep golden crust).
Remove from the oven and let it cool slightly on a wire rack. Slice and serve warm with plenty of butter!
