- Grease 2 or 3 clean, BPA-free cans with butter or ghee.
- Mix flours, salt, and soda together in a large bowl.
- Stir molasses into buttermilk and add this to the flour mixture; stir to incorporate all ingredients, but do not overmix. Fold in raisins.
- Spoon batter into prepared cans. Fill each can no more than ⅔ full. Cover each can tightly with a piece of aluminum foil.
- Place the cans on a rack inside a large pot. (A canning or stock pot works well). Pour boiling water into pot until it reaches about 1 inch deep. Cover the pot.
- Simmer, checking the water level periodically, for about 1½ hours.
- Remove the foil from the cans. The top of the bread will still appear a little moist, but it will be firm to the touch. Insert a thin digital thermometer to check the internal temperature of each loaf. (It should be 195°-200°F).
- Invert cans on a wire rack and cool for 5 minutes. Tap each can firmly on the counter to loosen the loaves. They should slide slowly out of the can. Finish cooling on the rack and wrap tightly when cool. Store bread in the refrigerator.
If you are using non-sprouted flours, soak them in the buttermilk overnight before mixing in the rest of the ingredients. The soaked mixture will be somewhat dry, but refrain from adding additional buttermilk or the finished product may be too moist to hold together well.