One of the world's most influential burger experts and a legendary New York pastry chef will headline Wellington On A Plate this year, as the festival expands to 230 venues across the region.

The annual event — the largest culinary festival in New Zealand — runs across August. This year's programme includes 170 participating restaurants for Burger Wellington, more than 60 events for the Dine Wellington programme, and a returning Cocktail Wellington competition.

WellingtonNZ chief executive John Allen said the festival was "the single biggest week for hospitality" in the capital, with last year's edition generating $34 million for the local economy.

Headline guests this year include Burger Beast founder Sef González and pastry chef Natasha Pickowicz, who will run masterclasses out of Le Cordon Bleu's Wellington campus.