yes one of my favorite(along with my kids) spring early summer dishes is fresh cattails.
I suggest you pick from a non-polluted area with no septic tanks:laugh:
grab them as low to the ground as you can, and yank! then cut the stalk leaving about ten inches.
next you have to peel the outer layers off to get to the very tender "heart"...this will be slimy, that's normal.
then chop up the tender hearts into small pieces about a 1/4th" thick and rinse thoroughly.
then cover with water in medium sized pot and bring to a boil...boil for about 12 minutes or until tender, strain...add some butter and salt and enjoy!!! tastes like corn on the cob.