‘We work closely with people like Polly Russell (the British Library’s food historian) with specific targets in mind,’ he explains. ‘For example, we might want to put a new fish or seafood dish onto the menu, or learn more about when chocolate first made its way into confectionery. She’ll know which books to get out and get us started, otherwise it’d be like looking for a needle in a haystack. We’ll take a quick photo with our phones when we find something interesting, then it’s back to the development kitchen to start working out what we can do with what we’ve got. There’s no exact formula we can follow when developing a dish. The ones we think look easy end up taking a very long time and the more complex recipes tend to work out quicker – there’s no rhyme nor reason.’

One of the main challenges of working with historic recipes is that they’re nothing like what we’re used to today. As they’re often 300, 400 or even 500 years old, it’s more like reading little snippets and reminders of how a dish is put together, or comments on a certain flavour combination. ‘We’ll pick out what we think is relevant to our style of cooking and get to work,’ says Ashley. ‘Sometimes it stays quite true to the original idea, and other times it will go off in a different direction. But that’s the joy of development.’

Meat Fruit is one of the dishes truest to its original incarnation ­­and is an ode to the trompe l’oeil method of presentation, a sort of optical illusion on the plate. But there are others that, while inspired by past ideas, are reinvented for the present day. ‘We’re not trying to recreate old recipes exactly. They’re more like modern interpretations that keep our imaginations fired up and let us have a bit of fun.’

While the idea of rich chicken liver paired with tangy citrus is something we can all relate to, some of the more unusual dishes at Dinner took years until they were ready. Frumenty – a sort of festive hot spelt broth served with fruit and fish – is a bit trickier to imagine, but Ashley’s version of it takes pride of place amongst the starters. ‘We knew some basic things about the dish and the earliest reference we could find was from 1390, which included porpoise meat!’ he explains. ‘We recreated the dish as a mussel-infused spelt broth with lots of seaweed and mushrooms, some pickled lemon and sea vegetables and then a piece of braised octopus on top.’

Of course, with all this research, development and experimentation, some projects never see the light of day at Dinner. Having to admit a recipe just doesn’t taste nice or that you need to go back to the drawing board after hours and hours of work can be frustrating. But Ashley and his team have now got to the point where they can tell quite early on whether something has potential. ‘There are recipes that just don’t work,’ he says. ‘One we found, a kidney and sweetbread dish flavoured with rose and fennel, sounded so disgusting that we simply had to cook and taste it. We weren’t wrong – it was awful. I think cooks tended to use a lot of rose essence when they needed to cover up off flavours in meat, so we didn’t put a whole lot of work into the dish before we abandoned the idea completely.

‘No matter how much effort and research we put into something, at the end of the day it just has to be delicious,’ adds Ashley. ‘If someone doesn’t have any interest whatsoever about the history or story behind a dish, it still has to be an amazing plate of food. We’re very passionate about something we call ‘encapsulated flavour’, which we’ve been playing with since about 2000 at The Fat Duck. It’s all about having those little pockets and bursts of flavour and texture on the plate, rather than everything being equal and a singular, flat experience. We always approach recipe development with that in mind.’

Being able to fall back on the work done in the experimental and development kitchens next to The Fat Duck in Bray has been key to Dinner’s success. The collaborative nature of The Fat Duck Group as a whole means every recipe, note or bit of research is shared, and as it grows specialist arms are beginning to form which dedicate themselves to certain aspects of the business. ‘There are people who focus on Dinner, those who work with the pubs, The Fat Duck team and then a few chefs who do the exploratory stuff,’ says Ashley. ‘But it all links together and everyone is connected; if you mention you’re working on something then there’s almost always someone you can talk to who can help. We have a massive database and each restaurant has its own catalogue of recipes and research. On top of that there are all the books and the programs, so even if it’s one little part of a dish or recipe you have something to refer to.’

In 2015, Heston announced that he was closing The Fat Duck to take it to Melbourne, Austrsalia for six months – a pretty bold move, especially as it meant temporarily giving up the restaurant’s three-Michelin-starred status (although he confidently won them all back the very next year). After the six-month residency he opened the second incarnation of Dinner, giving Ashley another project to manage halfway across the world. Despite the jetlag, it’s provided his team with another great opportunity to delve into the history of a very unique country.

The menu is similar, but with a few important differences; the calf’s tail in Rice & Flesh (c. 1390) is replaced with kangaroo, for example, while the snails in the Savoury Porridge (c. 1660) are substituted for grilled abalone. But as the menu evolves, Ashley is beginning to realise that as a relatively new country (especially when compared to Britain), Australia’s culinary history is a completely different beast.

‘It’s very difficult to define what Australia’s national cuisine actually is,’ he says. ‘The most historically famous food there is the meat pie, but Dinner isn’t that kind of place. We could take the flavour combinations and ingredients to make some sort of spin-off, but what we now understand is that nostalgia is much more important to Australians when it comes to the food of their past.

‘One dessert we’ve made is based on an Aussie chocolate bar called Cherry Ripe, taking apart the flavours of coconut, cherry and chocolate and reimagining them in quite a refined, clever way. I think nostalgia has a role in Australia that we don’t have in the UK – we’d never create a dessert based on a Mars Bar, for example – but that’s because we have all that history to fall back on. In Australia, they’ve found a connection with the food and drink of their childhood instead.’

Running a two-starred restaurant in London alongside a second branch over 10,000 miles away is an astonishing feat. But it’s how Ashley, Heston and everyone else at The Fat Duck Group have helped document and present food history in a way never really done before that’s really impressive. While the general preconception (at least internationally) of British food tends to be boiled meat, boiled potatoes and a serious lack of flavour, they’ve uncovered a different type of cuisine full of playful tricks, exotic flavours and flamboyant dishes fit for kings. The kitchen might be all sleek induction hobs, sous vide water baths and digital scales, but the inventive flavour combinations and attitude of leaving no stone unturned shows a timeless passion that’s been in every great chef over the centuries. And if you’re really missing the pomp of a kitchen fit for royalty, then the liquid nitrogen ice cream trolley and fiery spit dedicated to roasting those incredible slices of pineapple help create that famous Heston sense of theatre.