Media playback is unsupported on your device Media caption Can you cook your Christmas dinner in a slow cooker?

There's a culinary revolution taking place and it's not in a hurry. Like many things from the 1970s, slow cookers are back in fashion with some retailers reporting sales up by a third in recent years.

Driven by the trend for slow-cooked meats such as pulled pork, and their general cost effectiveness, the kitchen gadgets are making their case for an essential piece of kit.

BBC News Online has taken a look at why people are falling in love with their slow cookers all over again - and even tried cooking a Christmas dinner in one.

"I love my slow cooker," said Verity Mann, head of testing at the Good Housekeeping Institute.

"It's a brilliant piece of kit and there's a lot of nostalgia around them, with people looking at old recipes. I think they've become more popular over recent years because they've been designed to be even more convenient."

For those not yet signed up to the slow cooker movement, they are all-in-one electric cooking pots that cook food at a slow and steady rate, using very little energy.

Got a slow cooker question? Email us at england@bbc.co.uk, ask us on Facebook or tweet it to @BBCEngland. You can also find our money saving Christmas dinner tips on BBC England's Pinterest board

The rise and fall of the slow cooker

Image copyright Jarden

In 1936, inventor Irving Naxon applied for a patent for a cooking device in the US that was portable and would heat food evenly. He started selling his device, the Naxon Beanery, in the 1950s.

In 1970, Rival Manufacturing acquired Naxon and, in 1972, the Beanery was rebranded as the Crock-Pot - the name slow cookers are still known by in the US.

Sales exploded in the 1970s as more women began to enter the workforce. Slow cookers allowed them to be at work all day and still produce a meal for the family.

At the height of the gadget's popularity, about 40 different companies were making their own version but the market began to cool in the 1980s, at around the time microwave ovens surged in popularity.

Source: CNET.com

Image caption Slow cookers claimed to make life easier for women in the 1970s, as mums could go out to work and still prepare a family meal

They fell out of fashion for a while as meals had a tendency to turn out brown and a bit tasteless and microwaves became more affordable.

Retailer Lakeland said the popularity of its slow cookers continued into 2016, with sales up a third compared to 2011.

Dozens of bloggers and writers have turned their attention to slow cooking and a huge social media community has evolved, all sharing their love of slow cooking.

Amazon says two of its best selling cookbooks in the UK are specifically for slow cookers and Slow Cooker Kitchen's Facebook page has more than 1.9 million likes.

One such blogger is Miss South, who has put together a book of recipes after two years of research, which at one point included having six slow cookers on the go at once.

"Don't expect to get amazing meals if you don't use good ingredients," she warns. "It's a slow cooker, not a miracle worker."

Why do we love you so? Natalie Hardwick, features editor, BBC Good Food Magazine

Image copyright BBC Good Food

Slow cooker recipes are some of the most popular on our website and we see huge spikes in traffic when we mention them on our social media channels or in our newsletter.

As well as recipes, people love reading cookery tips on how to use slow cookers, and advice on which ones to buy, which makes sense as it's such a practical piece of everyday kit.

They keep getting more popular, probably because people are cooking with cheaper cuts of meat, are looking to reduce their energy bills and lead such busy lifestyles.

They're also very affordable, so they pay for themselves in no time. We know slow cookers are popular with students too, so this is definitely a cross-generational trend.

Image copyright Thinkstock Image caption Slow cookers are becoming an essential piece of kitchen kit

Miss South started experimenting with her slow cooker after having to give up several jobs due to having ME.

"I was struggling to feed myself - energy and cash-wise - so I started to blog about feeding myself or I would have just ended up living on sandwiches and crisps.

"Slow cookers are very low energy, both in terms of power and my energy."

And there is no doubt that its cost-effectiveness is one of the gadget's biggest selling points.

Price comparison website uSwitch says that although microwaves are the most energy-efficient way to cook, slow cookers "use just a little more energy than a traditional light bulb".

"There are some chefs who have lovely recipes where you slow roast meat in your oven for eight hours. That's very nice but it's very expensive and if you're on a fuel budget, you can't do it," said Miss South.

Slow cooker tips

Image caption Make sure you choose the right size of slow cooker

Use a dedicated slow cooker recipe, otherwise you can end up with too much liquid

Halve the quantity from a conventional recipe if you are adapting it for a slow cooker

Cut off the excess fat as it will pool in to a greasy mess on top of the dish

Use cheap cuts of meat - like pork shoulder and lamb shanks - or you'll totally miss the point of slow cooking

Always taste the food before it goes out. You need to finish off a dish, even if you've done it in a slow cooker, season it and add fresh herbs - treat your meal as if you'd spent six hours preparing it

When you're starting out, cook something you know, so you have an idea how it should turn out. Remember, too, that new models cook hotter than old ones

Don't cook green veg in them or things that are meant to crunch - soft and melting are the textures to go for

Don't keep lifting up to check the food

Make sure you choose the right size of slow cooker for your recipes

Source: Miss South and The Good Housekeeping Institute

But not everybody is a fan. Meike Beck, cooking director at the Good Housekeeping Institute, is one such naysayer.

"I actually hate slow cookers. There's a tendency for everything to look brown and taste the same.

Image copyright Thinkstock Image caption Slow cookers had a bad reputation for producing brown, watery dishes

"But thankfully more people are now inclined to cook. However, this isn't necessarily in correlation with confidence or skill, so this is an entry-level way to produce a delicious, healthy meal, and you take the risk factor out of it."

It's a sentiment echoed by Miss South." After I published my book, I had loads of feedback from older men, either widowed or divorced, who were cooking for themselves for the first time."

Slow cooking really is straightforward, there are a few golden rules to stick to, but people are becoming more and more adventurous.

"It's great to see classic cooking being done again by a whole new generation," said Verity Mann.

"People are buying cheaper cuts of meat and [with a slow cooker], the fibres are broken down and you can create good meals.

"They're also timesaving as it's minimal labour. I prep all my stuff the night before, chuck it all in and end up with a lovely meal."

From stews and curries to steamed puddings and risotto, it looks as if slow cookers will no longer be relegated to the back of the kitchen cupboard.