This is a rye "quick bread" (no yeast) from Iceland that is typically burried in a volcanic sand hot-spring to steam for up to 24 hours. For my variation, I used standard "play sand" mounded up the sides of a cast-iron dutch oven.
3 cups dark rye flour 1 1/2 cups all purpose flour 4 tsp. baking powder 2 tsp. kosher salt 1 tsp. baking soda 2 cups buttermilk 1 cup molasses
Mix all dry ingredients together, add wet ingredients to combine. Bake in water bath at 212 ° for 8 hours (or until done)