Prepare the loaf pan: Grease the inside of a 13x20cm / 5x9in loaf pan with butter.
Mix the dough: In a large bowl, combine all the dough ingredients. Use your hands to mix it all together gently to form a thick dough.
Shape the dough: Use a dough scraper to scrape the dough from your hands back into the bowl. Shape the dough with wet hands into one mass and then into an oblong that’s the shape of the loaf tin.
Coat with seeds: On a wide plate, combine the extra handfuls of seeds and roll the loaf in seeds so that it is well coated.
Ferment the loaf: Gently set the loaf into the buttered pan and check its temperature (it should be between 28°C / 82°F). Let the loaf ferment, covered with a tea towel, for 2-4 hours.
Preheat the oven: Preheat oven to 200°C fan forced (390°F). Place a shallow roasting pan in the bottom of the oven.
Bake the loaf: Place the loaf pan on the centre rack and add 1 cup (250ml) water to the roasting pan. Bake for 1 hour, rotating the pan halfway through.
Check doneness: The loaf should read 95°C/203°F on an instant read thermometer and seeds on top will be toasted.
Cool the bread: Turn the loaf out onto a wire rack to cool for several hours before slicing.