Continental Europe may long have looked, askance and appalled, at Britons’ ability to hit the sauce on an empty stomach, and then to keep on hitting it. Before hitting it some more.

But, equally baffling to foreign eyes, noses and stomachs is the UK’s consumption of a rich and strange array of actual sauces.

Handily for Spaniards, one of the country’s eminent cultural diplomats and noted gourmands has just produced a guide to what to expect – and what to reject – when confronted with the conundrum of the UK’s many condiments.

Ignacio Peyró, a journalist and author who is also the director of the Instituto Cervantes in London, begins his 1,000-word piece for Spanish Esquire with a wily disclaimer: “Railing against British food is a passion capable of bringing together not just visitors to these isles but also the locals themselves … Whether justified or not, the bad reputation of English food remains one of the most dependable things in this world.”

From there on, things are appropriately bittersweet. English mustard – “the most patriotic” of all British sauces – harbours “such a devastating strength that it scorches the unsuspecting palate as thoroughly as the most spiteful chilli”. Ditto horseradish sauce.

Peyró has the grace to acknowledge that Marmite isn’t really a sauce before dismissing it as “filth”, and moving on to mint sauce. Perhaps, he suggests, the herbal accompaniment is used to disguise the advanced age at which people in the UK like to eat their lamb. In Spain, he adds, they tend “more towards infanticide when it comes to matters ovine”.

Branston pickle is “a classic snack for drunk people”, while HP sauce is “a sickly-sweet, unsophisticated” barbecue-sauce-style affair consumed in “its hectolitres” with Sunday morning English breakfasts across the land.

There are, however, exceptions. Piccalilli – aka “mustard with other stuff”, aka “that noble Anglo-Indian spiritual creation” – is great with ham, he conceeds. Bread sauce, meanwhile, is a “splendid and vital accompaniment to a good Scottish partridge”, and Peyró can’t for the life of him fathom why “it’s had less success abroad than Ringo Starr’s solo career”.

And then there is the brown alchemy contained in a bottle of Lea and Perrins, which demands to be unleashed and applied liberally to a piece of Welsh rarebit – “as it is by all good Britons”.

For all his ribbing, Peyró, who has lived in the UK for two-and-a half years, is enthusiastic and knowledgeable when it comes to UK produce and cooking. He is a fan of its kippers, soups, fresh raspberries, oysters, fennel, “really, really good eggs”, and what he calls its “extraordinary range” of beers – even if many would not suit a Spanish summer afternoon’s drinking.

“I always defend British food and I think it’s not as well known as it should be,” he told the Guardian.

“You’ve got wonderful things, such as pies – chicken and leek pie, for instance, is a marvellous thing – which are lovely because they’re sort of ancient foods; a bit like Henry VIII’s tupperware. And besides, a pie is always something special. Then you have the roasts. You just can’t argue with roast beef.”

But, as with his heretical stance on Marmite, there are some things he fears he will never get his head or mouth around.

“To be honest, I don’t think anyone from the continent ever gets used to rhubarb,” he admits.

“People say, ‘Oh, but it’s such a beautiful colour!’ But no. You do what you can, but it’s impossible.”