There was, metaphorically speaking, a little extra spice to flavour a famously competitive culinary contest being waged for the 30th year in the West Yorkshire village of Mytholmroyd yesterday.

The World Dock Pudding Championships - boasting nothing more transcontinental than the defending champion from Halifax, four miles along the Calder Valley - had been pepped up by climatic patterns that have done strange things to dock plants this year.

An unseasonally warm winter gave rise to an early dock harvest, prompting fears that the leaves - the part used by those aiming to rustle up the world's finest pudding - would be tough and unappetising. The competition was subsequently brought forward a month, for the first time in eight years, bringing more tender leaves.

"The time change does add something," said Sandra Wickham, one of the championships' organisers, whose daughter Rachel was fighting it out in the junior competition. "The leaves will be smaller and fresher."

And so the tension piled up for world champions Trevor and Joan Whitworth and their 23 challengers - the largest field in years and the maximum permitted. "Any more than 24 and the judges get overfaced," Mrs Wickham said. "They forget what they have tasted."

The puddings - a breakfast dish also comprising nettles, oatmeal and onion - were cooked at stoves on the stage at Mytholmroyd's community centre and solemnly removed to the judges' adjacent room - each plate numbered to ensure no hint of bias. "The judges are looking for taste and texture," added Mrs Wickham. "Not too sloppy - so it sits nicely on the plate. They want the consistency of spinach."

The delicacy is dated by some locals to the days of 19th century poverty when dock leaves were eaten because they cost nothing. It can be made only from the young leaves of the dock plant, relatively rare but abundant in the Calder Valley where all competitors have a special place to pick them.

The Knowhere guide to the town of Hebden Bridge describes the pudding as "a strange delicacy made by boiling weeds and oatmeal ... foul and slimy, and of course, good for you." Mrs Wickham only agrees with the last bit. "They've always reckoned it's good for the blood," she said.