I was looking to make Marco Pierre White's Dory a la Nicoise, but John Dory fish is quite a high-end, pricey fish which you will find in many fancy and high-end restaurants – while I am happy to give the recipe a try, I'd like to use a more common/affordable alternative, as I am no professional chef who is looking to risk wasting the high cost.
Having looked around in different forums (e.g. flyertalk), I have seen it compared to Dover sole, but there isn't much else to go on, so I turn to the folks at cooking SE.
In terms of flavour and texture, what is a good alternative to John Dory fish? A cheaper, more common fish suggestion would be preferred.
Special consideration to the recipe and complimentary flavours involved will be thoroughly appreciated, but is not necessary, as I intend to respect the site's ethos for general Q&A rather than highly-specific and only relevant to me Q&A.
Best Answer
Looks like what you read was correct. From Fine Seafood Co here is a description of the John Dory fish. (As many in the US will not be familiar.)
(Emphasis mine.)
Per my research, Dover Sole seems to be the first choice to use as a substitute for John Dory. Another that I found mentioned quite often was Turbot. But that seems to be even more expensive than John Dory.
Others listed as possible substitutes on Cookipedia are: Bass, Grouper, Snapper, Emperor, and Halibut.
Here's a link to the Guide on Fine Seafood Co with descriptions of many other fish. (No endorsement intended - just good information.)