The £10m campaign, developed by Kellogg’s in collaboration with agencies Leo Burnett and DigitasLBi, aims to create a national debate using the hashtag #myperfectbowl.
A series of TV ads features real people from around the UK talking about their preferred serves – which include niche styles such as topping them with peanut butter, apple juice or water.
The brand said that the campaign comes from the insight that while Corn Flakes is seen by a large number of consumers as a "much loved" product, there is little consensus on how they should be enjoyed.
The campaign was created by copywriter Emma Banks and art director Noe Vavilovas for Leo Burnett, and directed by Oscar Cariss through Annex Films.
Gareth Maguire, marketing director for Kellogg UK & Ireland, said: "Kellogg’s Corn Flakes is the iconic cereal brand; everyone has a perfect way to enjoy their Corn Flakes and that’s what we’re tapping into with this campaign.
"We’ve seen a change in what people eat for breakfast but cereal remains the number one choice in the UK. And we know from our research that Kellogg’s Corn Flakes are the nation’s most loved cereal brand. So with this campaign we hope to further strengthen this relationship between consumers and our brands.
"After a long break, it’s time for us to start talking about Corn Flakes again and there’s no better way of doing this than through the words of our loyal fans."
Sales of Corn Flakes have fallen for each of the last four years and in the year to October 2016, they were down more than 10% in value to £47.3m (Nielsen). UK sales of all breakfast cereals fell last year by £77.6m (5.5%) to £1.34bn.
Corn Flakes is the UK’s sixth best selling cereal brand, after Weetabix, Quaker, and three other Kellogg’s brands – Crunchy Nut, Special K and Coco Pops.