Celebrate World Gin Day with the Queen's favourite gin cocktail recipe

June 13 is World Gin Day, and we can't think of any better way to mark the occasion than by sitting down with a fresh gin cocktail — the Queen's favourite one, to be precise.

A royal lover of gin, Her Majesty has reportedly been enjoying cocktails made with the spirit for decades.

And while she does love a classic gin and tonic, former royal chef Darren McGrady revealed that one of her favourite drinks is a gin and Dubonnet.

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"That's her favourite drink," he told CNN in 2017, but don't think the Queen is guzzling down cocktails with every meal.

"She doesn't wake up in the morning and have a large gin and tonic," McGrady added. "Just in the evening. She certainly doesn't drink four glasses a day."

But what exactly goes into a gin and Dubonnet, and can you make one at home?

The answers are: exactly what's in the name, and yes!

Dubonnet, or Dubonnet Rouge Grand Aperetif for the fancy people, is an aromatic French beverage blended up from red wine, herbs and spices.

It packs a flavourful punch on its own, so it doesn't need much dressing up when you add it to gin.

According to Hello! magazine, the Queen's recipe for gin and Dubonnet is simple: one part gin and two parts Dubonnet over a lot of ice. Add a lemon slice and you're done!

That's not the only way to enjoy the classic cocktail though, the Dubonnet website offers a slightly different recipe.

"Combine all ingredients in a mixing glass, add ice and stir until well-chilled. Serve up in a Nick & Nora glass or rocks glass. Garnish with an orange swath," it reads.

So why not branch out this World Gin Day and try something new with the Queen's favourite gin cocktail?