re: Substitute for seafood/shrimp stock for crawfish étouffée?

You can use water if your tails are good and fatty or you have the fat from boiled crawfish. You can use it anyway, but it's a little weak, I think.

BB, using the chicken product doesn't make it taste like chicken. Chicken stock or broth is a pretty standard sub for seafood stocks. Sounds odd, but it is.