In the BBC Three comedy show Miss Holland which aired in 2018, the monarch's butler Grant Harrold spoke about British etiquette, sharing an insight into the Queen's favourite tea and how to prepare the perfect brew.
WATCH: What the Queen eats in a day
Speaking about the Queen's preferred brands, Grant revealed: "I am sure the Queen enjoys her Assam or her Earl Grey the traditional way, made with tea leaves in a teapot and poured into a fine bone china teacup.
"She will also use a strainer. It is also a myth that members of Royalty use their pinky when drinking, I have never seen that happen once."
The Queen shows us how to drink tea
Although the exact brand has not been revealed, Twinings released a special, limited-edition tea - which was described as being similar to a traditional breakfast tea - to celebrate the Queen's 90th birthday, so perhaps her Majesty added this to her tea cabinet!
The Queen's royal butler has revealed she always pours tea before milk
Wondering why the royal family always stick to their milk-last rule? Grant said that since the 18th century, the "proper" way of brewing tea has been to serve tea before milk, and this is something that the British royals adhere to.
The tradition began when potter Josiah Spode created bone china teacups - the expensive and high-quality china became increasingly popular as it didn't crack when it was filled with boiling hot tea. However, those who couldn't afford bone china continued to pour milk into their teacup first, meaning the tea or milk first debate quickly became a status issue.
Grant Harrold appeared on BBC Three show Miss Holland
The butler also revealed the steps to prepare a royal cup of tea; pour the tea into the cup from a teapot, add milk to the cup after the tea and never before, stir back and forth (never use a circular motion and never touch the sides). Lastly, you should always sip from the cup and never slurp.
And while she has staff to see to her every need, the Queen is no stranger to making her own cuppa on occasion - if in doubt, do it yourself, right?
Back in 2019, the 94-year-old personally made a builder a cup of tea while he was carrying out work at Buckingham Palace. It was reportedly "builders tea", as he had requested, served with two sugars in a mug.
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