Prince Harry proposed to Meghan Markle during a cosy night in over a roast chicken.
In their first joint television interview, the happy couple revealed how Harry got down on one knee to pop the question and how Ms Markle could not wait to say "yes".
Harry said the proposal came a few weeks ago while they were at his home, Nottingham Cottage at Kensington Palace.
"It happened a few weeks ago, earlier this month, here at our cottage; just a standard typical night for us," the prince said.
Ms Markle added: "Just a cosy night, it was - what we were doing just roasting chicken and having ..."
Harry said he was "roasting a chicken, trying to roast a chicken".
"It was just an amazing surprise" - Meghan Markle on the moment Prince Harry proposed to her https://t.co/7pnNzobbc9 #royalwedding pic.twitter.com/JkSwTAfnDt— BBC Breaking News (@BBCBreaking) November 27, 2017
Ms Markle described it as "just an amazing surprise. It was so sweet and natural and very romantic. He got on one knee."
She added: "As a matter of fact I could barely let you finish proposing, I said - can I say yes now?"
The pair are to marry in a church wedding in the spring next year
Harry revealed how they had "hugs" after the proposal and he handed over the ring.
Prince Harry said: "She didn't even let me finish, she said 'can I say yes, can I say yes' and then were was hugs and I had the ring in my finger and I was like 'can I - can I give you the ring?' She goes - 'oh yes the ring'.
"So no it was - it was a really nice moment, it was just the two of us and I think managed to catch - catch her by surprise as well."
They talked about their 16-month relationship and how they never went more than two weeks without seeing one another.
Ms Markle said: "I don't think that I would call it a whirlwind in terms of our relationship, obviously there have been layers attached to how public it has become after we had a good five, six months almost with just privacy, which was amazing.
"But no, I think we were able to really have so much time just to connect and we never went longer than two weeks without seeing each other, even though we were obviously doing a long distance relationship. So it's - we made it work.
The pair said they were introduced by a mutual female friend in July 2016, but declined to reveal her name.
Harry told how they camped out under the stars in Botswana a few weeks after they met when Harry persuaded Ms Markle to join him on holiday.
Harry said: "Then it was I think about three, maybe four weeks later that I managed to persuade her to come and join me in Botswana.
"And we, we camped out with each other under the stars, we spent, she came and joined me for five days out there, which was absolutely fantastic."
Ms Markle revealed how they took "the time to be able to go on long country walks and just talk".
Ms Markle has met the Queen a couple of times and described her as an "incredible woman".
It was also disclosed that she had become a firm favourite with the corgis.
Describing being introduced to the Queen, Harry's grandmother, Ms Markle said: "It's incredible, I think, you know, to be able to meet her through his lens, not just with his honour and respect for her as the monarch, but the love that he has for her as his grandmother.
"All of those layers have been so important for me so that when I met her I had such a deep understanding and of course incredible respect for being able to have that time with her.
"And we've had a really - she's, she's an incredible woman."
Harry added: "And the corgis took to you straight away."
To which Ms Markle replied: "That's true."
Harry joked: "I've spent the last 33 years being barked at - this one walks in, absolutely nothing."
Ms Markle, who has two dogs herself, said: "Just laying on my feet during tea. It was very sweet."
Harry added: "Just wagging tails - and I was just like, argh."
Ms Markle said the Duchess of Cambridge had been "wonderful" to her, while Harry said both William and Kate had been "amazing".
Harry talked about how he kept the relationship secret before introducing Ms Markle to his brother and sister-in-law.
"It was exciting, I mean I've - you know, I'd been seeing her for a period of time when I literally didn't tell anybody at all.
"And then William was longing to meet her and so was Catherine, so you know, being our neighbours, we managed to get that in a couple of, well, quite a few times now, and Catherine has been absolutely amazing, as has William as well, you know, fantastic support."
Ms Markle said of Kate: "She's been wonderful."
Harry spoke of the support his family had given him.
"The family together have been absolutely, you know, a solid support, and my grandparents as well have been, have been wonderful throughout this whole process, and they've known for quite some time," he said.
Harry and Ms Markle, whose engagement was announced by the Prince of Wales on Monday, gave the interview to the BBC's Mishal Husain.