The two fish required for this must be different.

For example Rosy Bitterling and Soho Bitterling

The two fish do not have to be different, using two of the same category is just a trick you can use to use your entire stock up. So if the recipe calls for 2 fish and you have 3 rosy bitterlings and 3 soho bitterlings you can cook with 2x rosy's and then 2x soho's and then 1 of each. You can also use this same principle on any other category like grain (recipe requires 2x grain: use 1 wheat and 1 potato for example).

For dried fish, I had no problem using 2x green or better dried fish, but when I tried to use 2 Dried Sandeel (white), I didn't have great success. It did succeed at times, but failed constantly.

that recipe is wrong, i tried it over and over and got frustrated. The actually recipe is "2 fish, 3 olive oil, and 2 salt"...

confirm with same fish dray one and use 2 dray fish 1 fish 3 olive oil 2 salt

The recipe is correct: 1 fish, another different fish, salt, oil.

At Artisan cooking level, can confirm this works with 1x olive oil + 2x salt + 4x dried white fish. You can use 4x of the same dried white fish, or 2x dried fish A + 2x dried fish B. I was getting success+fails using only 2x dried white fish. Also success+fails using 3x dried white fish. No fails using 4x dried white fish (4x same type _or_ 2x type A + 2x type B)

Combinations that work: 2 white fish, 1 green/blue/yellow fish, 4 dried white fish, 2 dried green fish, 1 dried blue/yellow fish

At cooking artisan level 9, used [b]two different white fish, success 50 %. With 2 same green fish, success 100 %.

the recipe failed with 2 dried fish, but got 100% ratio 100 times in a row using 2 olive oil and 2 salt instead

With guru 3 work with 1 dried fish 1 oil 2 salt