Sweet Potato/Haddock/Spinach Soup Recipe?

[PuckyMup]

Does anyone have a fool proof recipe for the above please? Waitrose used to do a REALLY yummy soup of the above but its been discontinued so can someone help?!

Original here

My suggestion would be to make a basic "Cullen Skink" recipe, substituting Sweet Potato for the normal potato, then sweat off some spinach, cut it up finely and stir it through before serving. It might not be the same, but it shouldn't be bad.

Thank you :)