Meghan Markle revealed Prince Harry's favourite meal during her appearance on MasterChef Australia on Sunday night.

The Duchess of Sussex, 44, who guest-starred on the popular Channel Ten reality TV show, was asked by series judge Jean-Christophe Novelli what her preferred dish was to cook for her husband and their two children - Archie, seven, and Lilibet, five. 

The former Suits actress admitted it was a 'tough' decision to make given the different taste preferences in her famous family. 

'It's a tough one because I have a lot of palates to appease. My husband, being from the UK, loves a lot of meat, potatoes, cream sauce,' Meghan began.

'As a California girl, I like a grilled fish, grilled meats, citrus. I just like using lots of really pure natural herbs and spices. I like heat in my food, anything with spices.'

She revealed that her love of spicy food was shared by her husband. 

'He can handle a really good curry! We just do a lot of barbecues, whatever is seasonal. The kids are great eaters, we are very lucky on that front,' she said.

Meghan later squealed with delight when she received a surprise FaceTime call from Harry, 41.

She was taste-testing the finalists' dishes when a stagehand walked onto the set carrying a mobile phone and told her she had a call.

'Hi, my love! My husband's here!' an excited Meghan told the studio, and then pointed the camera at judges Poh Ling Yeow, Jean-Christophe and Sofia Levin, telling Harry: 'I'd like you to meet the judges!'

'G'Day! What's going on? Have I interrupted something important here?' Harry joked.

'Well, we are actually in the middle of tasting all the dishes. We have four incredible cooks here! It's amazing, they are so talented!' Meghan said.

'I can see the chandeliers in the background, they look very nice... wonderful!' Harry said.

He then asked to see the contestants' dishes and Meghan panned the camera over them.

'I wish you could try this. These dishes are fantastic, really great dishes, there's a hot sauce and it is so good!' she said, cheekily adding: 'I think it might be too much for you though.'

'I will leave you to enjoy it. All is well here, see you later,' Harry said as he waved goodbye to his wife while the studio erupted in applause.

Earlier in the show, Meghan proudly boasted that both her young children enjoy eating Brussels sprouts.

For her guest spot, contestants of the hit show were asked to create a 'dish fit for a Duchess' using ingredients she handpicked from the pantry.

She asked them to whip up a dish using ingredients like honey, macadamia nuts, citrus, edible flowers and celeriac.

As she unveiled a table laden with seasonal produce, Meghan told the contestants 'My kids eat Brussels sprouts', as Poh could be heard saying 'That's impressive'.

As for her family's favourite dessert, Meghan said that she encourages her children to pick fruit from the garden of their multimillion-dollar home in Montecito, California, but the family often enjoy pudding.

'The kids jump in a lot, especially with the garden. I think it's really... It's such a nice luxury to be able to have so much space and things to cook. And if they say, "Mama, can I have dessert?" You say, "If you can pick it, you can have it,"' she explained. 

'No, you can't pick chocolate, which is great. So, you can go pick a nice piece of fruit or whatnot. But, no, we always have a nice, as my husband would say, pud after dinner. But I think what's really sweet is that they all chip in. Family time, I think, is really key to connect through food. So, as many meals as we can do together, we always do. It's beautiful.' 

During the programme, Meghan praised finalist Petro Papathomas, saying his celeriac ice cream dessert featuring pickled apples and a hazelnut crumb was of exceptional quality. 

'The execution is beautiful. To be that creative and courageous, to make something new, you did it! It feels very Michelin star to me,' Meghan told Petro, who advanced to the semi-finals.

Meghan applauded Petro's work before telling the judges: 'Oh my gosh, I have loved it! I can't wait to go back to the hotel and tell Harry all about it!' 

Throughout the programme, Meghan had a few words of wisdom for the contestants as she acknowledged 'there is a lot of pressure in this kitchen'. 

'I don't like to cook that way; I like to cook in a really relaxed fashion,' she continued.

'So, all I can say to the competitors is to just remember to have fun, to keep a sense of humour about it, and to cook from the heart.'

Meghan added that 'food and cooking are how I show my nurturing and love for my friends, family and my kids' in a nod to her children.

She told the contestants: 'The hope is that you'll really hone in on one [item] as your hero item. These are all things that, for me, feel really nostalgic. And I love if there's a connection that you can find when, as you're cooking something, you ask: what is the story behind it? It almost feels like an heirloom, right? What is something from your family or from a memory, something sentimental that we can also taste as we taste your dish?' 

At the start of the show, Meghan insisted that she did not want to be called 'Duchess' as Poh introduced her.

'Welcome. Do I call you Duchess?' Poh asked after giving her a warm hug.

'Oh, call me Meghan. Absolutely, yeah,' she said. 

After introducing herself as 'Meghan', she went on to declare her love for Australia, explaining the trip was a 'full circle' moment for her and Harry as they announced they were expecting Archie while visiting the country eight years ago. 

'Oh, we're so excited. We love Australia. We had the most sentimental, amazing time. We were here almost eight years ago. We announced we were pregnant with Archie at the time. So, it's full circle, here we are, but thrilled to be here with all of you and taste some really good food. I've heard you've been cooking up a storm this season,' she said.