‘Rēwena’ is the Māori term for the fermented potato mixture used as a raising agent. It is difficult to find the exact history of Rēwena Bread, but it has been suggested that previously it was made with ground-up bulrush plant and water, and baked over hot rocks.
Cook the potato in the water. Once cooked, set the pot aside until the water is luke warm, then mash the potato with the sugar and plain flour. Continue mixing until a gluey texture forms. Transfer the mixture into a large glass jar and cover. Leave in a warm place until the mixture forms bubbles and doubles in size.
Once the bug is ready, combine the first lot of flour, sugar and salt into a large mixing bowl, and make a well in the centre of the bowl and add the bug.
Add water to the mixture in two lots, combining the water thoroughly with the mixture each time.
Turn the dough onto a flour dusted bench, and gently knead the dough for no more than 10 minutes.
Place the dough into a greased bowl, cover and leave in a warm place to prove (Generally 2-3 hours).
Remove the dough from the bowl, and punch the dough to remove any air bubbles, then gently knead for a further 2 minutes.
Cut the dough in half and place into two greased loaf tins.
Cover and allow to prove for a second time(Generally takes 45 minutes to 1 ½ hours).
Once the doughs double their sizes, make huge cuts across the top of the bread, and place into a preheated oven at 180 degrees, and bake the bread for approximately 35-45 minutes.