That time the Queen made a cup of tea for a builder at Buckingham Palace

For mere mortals, the process of meeting Queen Elizabeth II is usually quite carefully controlled and guided by royal tradition.

Typically, people are expected to bow their necks, curtsy or shake hands on meeting the monarch, and to use her formal address — "Your Majesty" and subsequently "Ma'am."

However, one construction worker threw the rulebook entirely out the window when he encountered the Queen while on the job at Buckingham Palace.

In an upcoming documentary, a royal upholsterer recalls how his friend, a builder, unknowingly accepted an offer from Her Majesty to make him a cup of tea.

As The Sun reports, he was busy dismantling a desk at the time, and his view was therefore obscured when a woman entered the room to ask if he'd like a cuppa.

"Yeah. In a mug, two sugars. Builders' tea," he replied unceremoniously, using British slang for a strong tea brewed in a mug, rather than a teapot, with a dash of milk.

"I don't want any of that nonsense I had the last time I was here, all that fine china and all that saucer stuff."

(Yes, he really did turn his nose up at a tea served in Her Majesty's fine china.)

Seemingly unbothered, the mystery woman left the room and returned with the brew, telling the builder: "I've put your tea on the table here."

When the builder looked up, he realised it was the Queen herself who'd delivered the cuppa.

LISTEN: The Windsors podcast delves into the extraordinary life and reign of Queen Elizabeth II. (Post continues.)

The story is told in Channel 5 four-part series Secrets of the Royal Palaces by Kevin Andrews, the Queen Mother's upholsterer.

It comes as little surprise to know Queen Elizabeth is a fan of tea. (Can you imagine a British monarch who didn't...?)

Former palace chef Darren McGrady has previously said that in the morning, her brew of choice is Twinings Earl Grey tea with a splash of milk and no sugar.

Interestingly, Twinings has a long association with the monarchy, having held a royal warrant since 1837.

The Queen is said to be so fond of the tea, she takes a stash of it with her when she travels.

In 2018, royal butler Grant Harrold shared more light on the monarch's tea habits, saying she favours Earl Grey and Assam.

"I am sure the Queen enjoys her [tea] the traditional way, made with tea leaves in a teapot and poured into a fine bone china teacup. She will also use a strainer," he said.