This classic Irish quick bread uses baking soda (as the name implies) as its leavener. It's usually made with buttermilk and is speckled with currants and sometimes caraway seed. Before baking, a cross is slashed in the top of the loaf. The purpose of the cross, legend says, is to scare away the devil.
From The Food Lover's Companion, Fourth edition by Sharon Tyler Herbst and Ron Herbst. Copyright © 2007, 2001, 1995, 1990 by Barron's Educational Series, Inc.