The recipe for Iceland resident Viktor Sveinsson's bread calls for one unique step: add in Mother Nature. In a short movie entitled "Volcano Bread," filmmaker Alison Grasso follows Sveinsson as he bakes a rye loaf in a natural hot spring in Iceland, Eater reports.

Sveinsson lives in Laugarvatn in Iceland’s Golden Circle, a 190-mile loop throughout the country that contains a series of hot springs, volcanoes, and national parks. The small lakeside town features three hot springs that are used for heating homes, a local spa, baptism—and of course, baking bread. Sveinssen uses a hot spring to bake Rúgbrauð, traditional Icelandic dark rye bread.

The natural oven reaches temperatures of up to about 212° F, the boiling point of water. Taking 24 hours to bake in a large pot and placed underground, Sveinsson’s rye bread—which is served with a rather large pat of butter—is described as "surprisingly sweet" by the baker. The recipe calls for four cups of rye flour, two cups each of wheat flour and sugar, four teaspoons of baking powder, one liter of milk, and a pinch of salt.

Check out a clip below from the doc that won Best Super Short Film at this year’s New York Food Film Festival.

[h/t Eater]

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