Princess Diana was known for being a trailblazer. She redefined royalty with her open and relatable attitude was also praised for her charity and humanitarian work.

But this isn't the only way the People's Princess kept things down to Earth. According to her former private chef, she was a big fan of a breakfast that many of us eat to this very day.

Instead of ordering something opulent like caviar or truffle, Princess Diana was very keen on a healthy start to the day. In a YouTube video, chef Darren McGrady said: "Her go-to breakfast was something called overnight oats."

We did mention that the royal was a trailblazer - and it seems that she was ahead of the curve when it came to her breakfast too!

The professional cook added: "Now, today, overnight oats are really popular. Everybody's eating them. But they date back to 2012. That's when you couldn't even go on social media without seeing a recipe for overnight oats. But Princess Diana was eating overnight oats almost 20 years earlier, in 1993."

Chef Darren revealed that Diana got the recipe after visiting a Swiss health clinic, where she enjoyed a meal called Bircher Muesli.

Apparently, she brought the recipe back home to the UK and asked the cook to make it for her breakfast every day.

The night before breakfast, add one cup of rolled oats to a bowl. Then, add one cup of freshly squeezed orange juice before letting the mixture steep in the fridge overnight.

The chef explained that you could use any type of oats other than quick oats. He added: "[Try] the rolled oats, in my opinion, they're the best."

In the morning, you will notice that the oats have swelled up as they've absorbed most of the orange juice.

To prepare the breakfast, chef Darren adds in one cup of Greek yoghurt to the oats. This serves as a good source of protein for the meal.

Fold in the yoghurt gently with a spoon, before adding in one tablespoon of honey. The chef explained: "Now, I like to use raw honey, and I'd say with the raw honey, just do that to your taste. If you like it really, really sweet, then obviously put a little bit more in, but not too much."

He then went on to add the juice of one lemon. As for the rest of the ingredients, it's all up to personal preference.

Darren said you can add toppings like berries or seeds. However, Diana's original recipe used half of a honey crisp apple grated on top of the oats. She was also a fan of fresh blueberries and toasted walnuts.

To serve, mix everything together and tip into a bowl. Garnish with more walnuts and blueberries and your royal breakfast will be ready to dive into!