They may be Parboiled before baking.
"The Myrtle Reed Cook Book"
Myrtle Reed
These tongues are to be sliced, Parboiled, and dried like meat.
"The Sun Dance of the Blackfoot Indians"
Clark Wissler
It is quite soluble in hot water, and in some localities this species of Helvella is always Parboiled-the water being thrown away-before it is prepared for the table.
"Studies of American Fungi. Mushrooms, Edible, Poisonous, etc."
George Francis Atkinson