Brown bread is the traditional accompaniment to baked beans, a true New England favorite. This loaf is cooked by steaming. To rig up a steamer, add 2 inches of water to a large pot; then place a brick or tin can in the center of the pot and set an empty 23-ounce coffee can (or 7- to 8-cup cylindrical mold) on top of it. Cover the pot tightly, and check it every 30 minutes to make sure there’s still plenty of water at the bottom.
In a large mixing bowl, whisk together dry ingredients. Add wet ingredients and sultanas, if you like, and stir to form a smooth batter.
Butter the mold thickly and add batter (to about one-third of the way). Cover the pan with buttered foil and tie it in place with a string.
Place the mold in a steamer pot over 2 inches of rapidly boiling water (you’ll need to add more water as it cooks). Cover and cook 2-3 hours, until a toothpick inserted into the center emerges clean.
Unmold on a cooling rack and let cool slightly. Serve warm, slathered with butter.