Bucking tradition, the couple have ordered an organic lemon and elderflower cake for their eagerly anticipated nuptuals in May. The confection will be covered in buttercream and decorated with fresh flowers. And unlike previous Royal weddings, there won't be a raisin in sight...
There is no official royal protocol around wedding cakes, but history would suggest that the multi-tiered, fondant-frosted fruit cake is a long-standing tradition.
Queen Elizabeth and Prince Philip's towering iced fruit cake was taller than your average Christmas tree. Prince William and Kate Middleton's eight-tier fondant fruit cake is rumoured to have cost €80,000.
Meghan and Harry, on the other hand, are the type of couple who like to have their cake, and eat it. They've eschewed the fruit cake, the fondant and the fuss, and opted for a decidedly homespun confection by Claire Ptak of east London's cult Violet Bakery.
"Knowing that they really share the same values as I do about food provenance, sustainability, seasonality and, most importantly, flavour, makes this the most exciting event to be a part of," said Ptak in an official statement released by Kensington Palace last week.
Ptak represents the new guard of cake maker. As bakers first and designers second, they don't want to make cakes that look too good to eat. They want to make cakes that beg to be eaten.
Julien Drapeau of French Wedding Cakes in Kildare puts the shift in choice down to the popularity of TV baking programmes and a renewed interest in food provenance. However, he says there was a time when clients were willing to sacrifice flavour for a show-stopping wedding cake.
"Ten years ago, I had people who told me, plain and simply, 'I don't care one bit about the taste. I just want it to look beautiful'."
Nowadays, he deals with clients who, like Meghan and Harry, want flavour first and foremost.
"The people who come to me with this style of cake in mind are food lovers," he says. "They love going to food markets. They love experiencing restaurants in France and Italy, and discovering new types of food. They want to do something that pleases them before everybody else."
Suzanne Brady of Cove Cake Design in Dublin agrees that palates have become more sophisticated. "Gone are the days of fruit, chocolate biscuit or lemon flavours," says the scientist turned cake designer. "[Clients] are more discerning of cake flavours, and more likely to go for exciting flavour combinations."
Julie Reardon, aka The Flour Artist, saw a gap in the market for simple, stripped-back wedding cakes when she went out on her own two years ago. Like Ptak, she specialises in buttercream and fresh flower wedding cakes - and she doesn't take orders for fondant-frosted cakes. "The focus is on the flavour," she says.
When Valerie and John Stafford got married last August, they opted for three deconstructed buttercream tiers by Julie Reardon.
"I think a lot of people get cakes to look at and not to eat. We wanted to enjoy our cake. And we didn't want a traditional style of cake because of the thick icing," says Valerie.
"I wanted to have more than one cake so Julie came up with the idea of having three separate tiers, deconstructed. My husband is a farmer so he cut down a tree to make the stands, and I sanded them down and varnished them.
"My mother-in-law is very traditional - she thinks it's important to bring the fruit cake home to freeze it -but even she loved it when she tasted it."
Contemporary cake makers may differ on the finer details, but they all agree that the traditional fruit cake has fallen out of favour as couples increasingly break with wedding cake tradition. Here are five trends that they're following instead…
Meghan and Harry didn't want piping, beading, latticework, or any of the other embellishment that characterised wedding cakes of old. Like the couple themselves, their choice of cake is relaxed and a little bohemian.
The rustic wedding trend introduced the earthier aesthetic for wedding cakes. The naked cake (where the layers of the cake are visible) was huge a few years ago, while the moreish drip cake is still popular.
Homespun wedding cakes are less about picture-perfect sugar craft details and more about all-natural decoration, like fresh fruit and blooms.
Overwhelmed by Pinterest and bombarded with choice, some couples choose to strip back their wedding cake to the simplest possible arrangement.
Wedding planner Sharon McMeel says many couples are opting for strikingly simple white-on-white wedding cakes.
"I'm seeing a lot of white icing and white flowers," she says. "It's a pared-back look for couples who don't want anything too fussy."
Julie Reardon (The Flour Artist) says an all-white cake can look very sophisticated with a simple accent of green foliage or naturally grown herbs.
"A really naturally textured buttercream with a few sprigs of rosemary is so effective," she says. "Plus, it's a little cheaper because you're not paying for the blooms."
Finicky pearl and piping detail is out of fashion but many couples still want a cake with the wow-factor.
Suzanne Brady says the trend for metallics and geometric designs reflect the current mood in design and interiors; Caroline Goulding reckons textured fondant designs are going to be huge next year while brush stroke, geode and handpainted cakes are all the rage on Instagram.
Sharon McMeel is dealing with an increasing number of couples who think of wedding cakes as an "older fashioned tradition". Instead, they're going for elaborate dessert tables, featuring mini cakes, brownies and cake pops.
The dessert table idea also appeals to couples who are conscious of waste. After all, nobody wants their wedding littered with half-eaten slices of fondant-lined fruit cake, scrunched up in paper serviettes...
Other couples are breaking the mould entirely and opting for ever-inventive wedding cake alternatives. Maja Binder of The Little Cheese Shop in Tralee says her cheese wheel wedding cakes, served with Irish pickles and natural crackers, are popular with couples who want a "vintage natural style", while Julien Drapeau's croquembouche wedding cakes are popular with foodies and Francophiles.