Bertoni Casalinga brings lasagne burgers to Balmain

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Pack away your burger buns Sydney chefs, we have a winner in the extreme burger wars. The burger craze that has even swept up our fine dining chefs, inspiring Neil Perry and Warren Turnbull to open burger joints, has also seen an explosion in offbeat combinations, from the roo burger to pulled meat and bolognese versions.

But chef Danny Russo's creation for the new-look Bertoni Casalinga in Balmain is extreme eating unlikely to earn any Heart Foundation ticks. Two pieces of lasagne, battered and fried, comprise the "bun", which encases a wagyu pattie, mozzarella and special Italian sauce.

"I thought he was mad. We were going to serve some Mylanta on the side, but it is the most amazing thing I've seen," says Bertoni co-owner Anthony Iacono. Russo, who wrote Bertoni's new menu, describes the creation as "so wrong it's right".

And he clearly knows his market. It is walking out the door at Bertoni, which has just had a major redesign, offering a more grown-up Italian look with dark timber.

The Balmain favourite is set to be joined by a new city sibling, opening mid September on the corner of Phillip and Bent streets in the CBD. No word yet if Russo's creations, which include a 'breakfast' carbonara with a fried egg on top, will join the city trek.