London’s The Artisan Bakery has developed a vegan brioche roll for burger specialist Patty & Bun.

The vegan bun is made using rapeseed oil in place of butter, one of the main components of brioche, as well as soya milk and nutritional yeast which The Artisan Bakery said helps to increase the bun’s sweetness.

It will encase Patty & Bun’s vegan Whoopi Goldberger burger, which features a tempeh and mushroom fritter, topped with pickled cucumbers, diced onion, double-smoked gouda vegan cheese, mustard, ketchup and lettuce.

 “The burger bun is the crowning glory of our burgers, so to compromise with something less than delicious would be unthinkable,” commented Fred Webster-Trussell, head chef at Patty & Bun. The chain has sites across London as well as one in Ship Street, Brighton.

Earlier this year, a Lantmännen Unibake study revealed consumers will pay up to £1.25 more for a burger if it comes in a gourmet bun.

Vegan bakes have been a focus for The Artisan Bakery recently. In March it unveiled a range of vegan pastries including a croissant, pain au chocolat and pain au raisin, which took six months to develop.