How did Jesus eat his? What would Jesus goo? We'll never know, because as the comedian Bill Hicks pointed out, nowhere in any version of the Bible does there seem to be any reference to "chocolate". Yet each year countless millions of people choose to mark the resurrection of Jesus Christ by ceremoniously unwrapping egg-shaped combinations of sugar, milk, cocoa butter and vegetable fat. Nowhere more so than in Britain, where around 80 million chocolate eggs are bought and consumed each year.

A sweet and harmless symbol of fertility and spring around the corner? A connection to our collective pagan past? An edible representation of the stone that was rolled from the tomb of Jesus? Possibly. But the Easter-egg market, worth around £200m a year in the UK, is also a microcosm of the wider food world, with fierce loss-leader price-cutting by the major supermarkets and issues of fair trade, ethics and waste packaging never far from the aisle. And if all that wasn't enough to bring you down from your sugar-high, enter the Meaningful Chocolate Company's Real Easter Egg, "a way of reclaiming the festival and communicating key aspects of the Christian faith in an attractive yummy gift".

It hasn't ever been thus. A few decades ago there might have been a handful of chocolate eggs to ponder: a nice ribboned one for your auntie, perhaps, and some aimed at very young children. But that was before the market demanded that every brand extend itself, and nowadays every chocolatier worth their salted caramel has to have an Easter egg to themself.

Look at them all lined up out there like artisanal, hand-crafted, organic, battery hens. Would madam like a "Sweet Finesse", Oriol Balaguer's sculptural egg (£150, Selfridges)? Or might sir prefer the "edible work of art" that is the Belgium chocolatier Boon's eggs in a cage (£120, Harrods). Valrhona chocolate, box designed by Vivienne Westwood, Ladurée, Prestat, Green & Black's, Hotel Chocolat, Thorntons, Lindt, Godiva… These are the names to be reckoned with at the top end of this year's Easter-egg wish list. But these eggs are doomed not to come first, because the big players in the chocolate world – Nestlé, Cadbury, Mars – have the vast majority of Easter-egg sales tied up between them, with Cadbury alone boasting a market share of about 50 per cent.

It is early March and the final day of production in the part of the vast Bournville factory in Birmingham given over to making "shell eggs" – the hollow heart of Cadbury's Easter-egg empire. While anyone expecting Roald Dahl-like rivers of chocolate will be disappointed, our guide for the day – Tony Bilsborough, 51, Cadbury's head of external communications – is every bit as entertaining and knowledgable about chocolate as the fictional Willy Wonka.

"There are a couple of myths about our eggs," he says. The first is that they seem to be in the shops earlier every year, when in fact the season has always been from 1 January to Easter. And the second is that the Creme Egg has got smaller, which it hasn't. Some bright spark did once think that if we made Creme Eggs available all year round it would triple sales, but we found that it damaged the brand, so although, unlike the shell eggs, we make them here every day of the year at a rate of 350,000 a day, we try to sell them only in the run-up to the Easter holidays – although, of course, it is up to the shops how long they choose to stock them."

Around us, the production lines stop and start with all the efficiency of an office photocopier. Where once there would have been hundreds of people manning the lines, now only a sprinkling of hairnetted workers are on hand to ensure the smooth running of the machines and oversee the quality of the product. Stop and chat and they might, like Lilavati Mistry, who has been working here for 20 years, tell you that they like their work but don't really feel like eating Easter eggs. Others, such as Milena Stepanovic, whose white factory-floor shoes have been stained Cadbury purple (Pantone ref: 2685C) from years of changing the rolls of wrapping foil, will diplomatically tell you that her family loves chocolate eggs.

No one seems bowed by the presence of press cameras or Tony Bilsborough, and the factory-floor banter flows faster than the conveyor belts of Creme Eggs, when we finally find our way to that part of the building. Here, a neon sign informs us that there have been 35,685 of the little fondant-filled fancies made on this shift so far. And though a ghost in the machine has temporarily hampered our chances of seeing things at first hand, Bilsborough is there to painstakingly explain the process. "Many people think the filling is pumped in," he says, "but in fact Creme Eggs are made in much the same way as the shell eggs – each half-mould is filled with molten chocolate; the white fondant has a greater density, so it pushes the chocolate to the sides of the mould; and then the yellow fondant, which has a greater density still, is squirted into one half before the two half-shells are put together."

If that sounds like a complex process to make a little chocolate treat that most of us won't think twice about before devouring, don't even try to get your head around the inner workings of the Cadbury empire. Founded in 1824 by John Cadbury, a Quaker who believed that if people drank more chocolate they would consume less alcohol, the company has since gone through enough mergers, demergers and acquisitions to fill an issue of the Financial Times. The Kraft takeover of 2010 caught the public's attention, but few people seem to know or care that Cadbury is currently owned by a company called Mondelez International Inc.

What this means in reality is that Bournville's two five-floor manufacturing blocks now produce Belvita biscuits, Philadelphia cheese, Kenco coffee and Terry's Chocolate Oranges alongside the iconic Dairy Milk bar and all those Easter eggs. But if the memory of John Cadbury and his sons Richard and George has faded slightly in the shiny modern age, there is at least the nearby "model village" of Bournville to provide a permanent link to the glorious purple patch of days gone by.

The original Cadburys would also surely approve of many of the activities undertaken today by the company they founded. Cadbury World is a thriving visitor attraction a short walk away from the production lines, sweetened every day by the sound of scores of chocolate- loving schoolkids. And, next weekend, a series of Easter-egg hunts will take place at more than 250 National Trust properties all over the UK. Such wholesome outreach activities beg the question of why Cadbury didn't come up with its own Christian Easter egg. "There is certainly a market for a Christian egg, though k we have no desire to incorporate specific Christian imagery into our eggs," explains Bilsborough. "In fact," he says, "for many years, we have deliberately avoided linking ourselves to religious imagery at both Easter and Christmas, because we believe that many would find a major chocolate company doing this both offensive and exploitative. Interestingly, the symbol of the egg pre- dates Christianity and goes back to a time when the egg was a symbol of rebirth at springtime. The word Easter is actually derived from the pagan god Eostre."

If there is such a thing as an authority on Easter eggs, that person is Lee McCoy, a 37-year-old online marketing consultant from Warrington, Cheshire. McCoy, a lifelong chocoholic and judge at the Academy of Chocolate awards, started blogging about Easter eggs in 2008, and has since acquired something of a reputation as an eggs-pert (one egg joke. In this whole article. Come on) in his field. McCoy points out that the other, often-forgotten, reason that people eat chocolate eggs at Easter is that many will have given something up for Lent, and chocolate is the ultimate indulgence. But the reason he is obsessed with Easter eggs is that he sees them as the ultimate in chocolate creativity, the MasterChef final of the chocolate world.

"There are so many varieties now and there is such a world of difference between the best and worst," he says. "The problem is that the major supermarkets still operate a pile 'em high, sell 'em cheap mentality, which means that some very talented people can't get a look in."

Is there a religious element to his love of Easter eggs? "My background is Church of England although I'm not practising. But that doesn't mean I'm not annoyed by how little attention the major commercial manufacturers place on that element. As a marketing man, I know you have to have a fantastic product. So if religion has a problem, it might be that either they don't have a fantastic product or they're not marketing it properly. If the Real Easter Egg gets people talking about religion, that can only be a good thing."

Ask McCoy what people should be looking for in an Easter egg and things start to get a little involved. He says to beware the word "artisan", as anyone can use it. He advises to be on guard against any egg with "vegetable oil" in the list of ingredients because this is much cheaper than cocoa butter and is often created by deforestation. Cocoa beans from the Ivory Coast are also, according to McCoy, generally a fairly low quality and are used mainly because they are more resistant to disease.

All of which is fine if you are dedicated to searching for the perfect chocolate egg, but not necessarily the key factors that will assist us in our scouring of the supermarket shelves. So what does McCoy think of most of the big-brand Easter eggs? He answers in one word: "Woeful." But then, in the research for this piece, naturally, I happened upon a new product from Cadbury that I had seen no sign of in my visit to Bournville.

Cadbury's Egg 'n' Spoon comprises four chocolate eggs in a purple cardboard carton. Each box comes with two small plastic spoons and the idea is that you lop the top off the egg and scoop out the filling, which is either chocolate or vanilla mousse. It is teeth-janglingly sweet and, no doubt, guilty of many of the crimes against chocolate McCoy points out. It is also exactly the kind of creative chocolate genius that made McCoy love Easter eggs in the first place. So should you shell out on one of the five-bunny-rated extravagances in the box (below), or just nip down to the corner shop for a bunch of crowd-pleasing Creme Eggs? You have one week to hatch a plan… 1

For details on Cadbury and the National Trust's Easter egg hunts, go to eastereggtrails.com. For Lee McCoy's reviews of Easter eggs of all shapes and sizes, go to easter-eggs.org.uk

A jolly good egg: Chocolate expert Lee McCoy’s verdict

Chokablok Billionaires Dynamite Egg

"This egg from Tesco is far too sweet – it brought on a headache. Looking at the ingredients it's understandable: each bite is about 52.6 per cent sugar which is, to my mind, excessive." 1/5

Paula Young Sea Salted Caramel Egg "The best mini egg: you can't get much more luxurious at this time of year than tucking into this." (£19.95, paulayoung.co.uk) 5/5

Paul Wayne Gregory mango chocolate egg

"This egg oozes refinement, sophistication and above all: talent. Despite costing £24.95, it's worth it and serves as a perfect example of why you should venture off the beaten track." (paulwaynegregory.com) 5/5

Green & Black's Dark mint Egg

"This egg uses the standard dark recipe from Green & Black's, which has that lovely strange, organic, farmyard edge. When it's mixed with the organic peppermint oil, however, I feel a little of that unique G&B's flavour is lost." 3/5

Ferrero Rocher Milk Chocolate Bunny

"I looked at my Tesco receipt and saw that I'd paid £2.99 for it and my heart sank. Even worse, after managing to munch on just about 10 per cent of it, I had just had enough. It's far too sweet and overpriced. " 2/5

Thorntons Black-Forest Gateau egg

"The best mass-market egg, this has the bitterness dark-chocolate fans will enjoy, but is so laden with cherryesque sweetness that it borders on addictive. At the edge of the mouth-feel there is a touch of coarseness and the flavour profile misses a part of the spectrum, but for a £9.99 egg from a volume-maker, it's the best you'll find." 4/5

Nestlé Quality Street Easter Egg

"There's not much I can say about the chocolate itself as I rate it as awful. Very sweet and tastes wooden. The worst egg I've tried. Bunny rating? Zero." 0/5

Hotel Chocolat Rocky Road To Caramel

"If you wish to over-indulge on sweet milk chocolate then this is one for you. At £27 for 490g, the price is a bit steep for most, but if you need the greatest visual impact for an Easter egg, then Hotel Chocolat is your best bet." 3/5

Montezuma's Eco Organic Dark Chocolate Egg

"The egg itself is lovely. Many people see cocoa nibs as being bitter, and they can be, but these add a fruity, sweet acidity and a touch of random crunch."

(£7.99, montezumas.co.uk) 4/5

The Real Easter egg

"Very sweet, but just under the level where I wouldn't be able to eat it. Apart from the sugar, there's a hint of hazelnut that adds interest. It's also competitively priced and raises awareness and money for charity." (£3.99, widely available) 4/5