At first blush, the decree seems prudent – the mere suggestion of seafood with cheese summons visions of unholy unions: a fish-flavoured pizza, cheddar slathered on salmon – or horror of horrors, the Filet-o-Fish.  

But reality, as ever, isn't so simple. In the hands of experts, rules can be broken and unlikely elements alchemised into pleasing flavours. Indeed, take a squint at the latest crop of menus across town and you might be surprised by how many couplings of fish and cheese you'll find.

We're not talking mounds of mozzarella, however. At hatted Italian restaurant LuMi Bar & Dining in Sydney, a thin ring of feta adds a touch of creaminess and acidity to slices of bonito and fermented cucumber. Newport newcomer Sotto Sopra offers carpaccio of albacore tuna over a spoonful of burrata with lemon, basil and bottarga. And Melbourne's Cafe di Stasio bakes scallops in the shell with bread crumbs, parmesan and parsley.

One cook who isn't afraid to sprinkle a little parmesan on his seafood is Adam Liaw. He says the mantra has only ever really applied to one cuisine – Italian – and is probably a product of the physical distance between the cheese-making and seafood regions of the country.

"It's very much an Italian thing and I also think it's a bit overblown," he says.

"Taking cuisine and heritage out of the equation there's absolutely no reason why you can't match seafood and cheese at all.

"The idea is the delicate flavour of seafood is overwhelmed by the strong flavour of the cheese but if that were a rule then you couldn't use seafood with any strong flavours."

Liaw sees the idea as more of a cultural taboo that has amplified over waves of Italian migration, saying cheese used sparingly like a seasoning is a guaranteed flavour-booster in many Italian dishes.

"You can just taste the difference – if you have a nice simple tomato-based prawn pasta and you grate a little bit of parmesan over the top, I defy anyone to tell me that doesn't taste better."

Fish and cheese have long graced the same plate in English and French cooking, says chef Russell Chinn, pointing to classic fish-and-cheese combos such as lobster thermidor and tuna gratin. He happily serves smoked haddock and gruyere croquettes, Welsh rarebit with smoked haddock and quiches with salmon and gruyere at Cupitt's Kitchen in Ulladulla.  

"It's a balancing act, making sure the cheese is not going to overpower the fish and that they complement each other."

Even in Italian cooking, the rule may be more myth than reality, says Italian chef Federico Zanellato of LuMi Bar & Dining, rolling off a list of time-honoured dishes that marry the two ingredients: mozzarella and anchovies; mussels with bread crumbs and parmesan; stuffed calamari with caciocavallo cheese; and tuna belly with pecorino cheese.

"I have never followed that rule – I knew it existed but it never made sense to me," he says.

Chef Alessandro Pavoni from Sotto Sopra and Ormeggio at the Spit agrees it's a bit of a misconception (exhibit B: a "bloody beautiful" traditional salted cod dish from Venice called "baccala alla vicentina", which is finished with parmesan), saying that if ever there were a rule then the current wave of Italian chefs is now gladly breaking it. Buffalo mozzarella with raw prawns is a big winner in his books, for example, as is calamari risotto with parmesan.

Still, the question remains – can you really sprinkle parmesan on your spaghetti marinara?

"It's overpowering and it's too rich ... I know Italian people who put it on but that's something I wouldn't do," Pavoni says. "I would rather put some grated lemon zest on top instead."

Let's take that as a no.