You don't have to bake your biscotti until they are hard enough to break a tooth, but I do prefer them hard so they hold up to being dunked in hot chocolate. If you prefer biscotti with a softer texture, you can just bake them for less time or skip the second bake all together. I usually sneak one piece of soft(er) biscotti after the first bake because it is chewy and delicious! But it just isn't really biscotti to me unless it is crunchy and dry.