Danish pumpernickel (rye bread) (rugbrød)

Combine the rye and bread flours, rye flakes and the salt in a large bowl. Pour over the boiling water and mix quickly with a wooden spoon to a dough. Cover and set aside for 10 minutes or until cooled to luke warm.
Pour the butter and treacle over the dough, sprinkle with the caraway seeds and yeast and then use your hands to mix until well combined.
Turn the dough onto a lightly floured surface and knead for 4-5 minutes or until the dough is smooth and elastic. Place the dough in a lightly greased bowl and turn to coat in the oil. Cover with plastic wrap and place in the fridge overnight to prove.
Grease a 10.5 cm x 21 cm (base measurement) loaf tin with melted butter. Punch the centre of the dough down with your fist and turn onto a lightly floured surface. Knead for 1-2 minutes or until smooth. Shape into a log about 10 long and place in the greased loaf pan, pressing down to fill it. Cover with plastic wrap and place in a warm, draught-free place for 1 hour or until risen slightly
Preheat oven to 200°C.
Combine the extra 1 tsp of treacle and ½ tsp water and brush over the top of the loaf. Sprinkle with combined pumpkin and sunflower seeds. Bake in preheated oven for 1 hour-1 hour 10 minutes or until cooked when tested with a skewer and sounds hollow when tapped on the base.
Stand in the pan for 10 minutes before turning onto a wire rack to cool. Serve in thin slices.