Soy sauce ice-cream on the menu at Luke Nguyen's latest restaurant

Luke Nguyen might have just jumped from travels in front of the camera on Vietnam's Reunification Express to a kitchen in Sydney's Royal Botanic Gardens, but he's lost none of his sense of adventure.

The TV chef has laboured on a new soy sauce ice-cream, sliding it on a dessert plate alongside miso caramel at Botanic House, the newly renovated and renamed restaurant in Sydney's most famous garden.

Nguyen sweated and fretted over the proportions of soy before he got just the right hit of savoury and sweet.

And he's not finished. "I want to do a fish sauce ice-cream at some stage," he says.

Botanic House is a brighter, lighter reimagining of the formerly tired and dark restaurant on prime Sydney turf.

All the window frames have been replaced, and blonde timbers, custom furniture and sculptures make the room barely recognisable.

The more accessible downstairs venue, Farm Cove Eatery, has also been given a makeover, but its menu isn't part of Nguyen's brief. Upstairs, which falls under the chef's domain, is where Nguyen is punching out his signature Asian food.

"I had to put salt and pepper squid on, it's Australia's national dish," he jokes.

But there's a touch of inspiration from the gardens, the squid topped with native peppers. There's a clever "roll your own" section to the menu with Vietnamese crepes ($22-$26) you fill with everything from tiger prawns to chorizo or mung beans and tofu. Just save room for the soy sauce ice-cream.

Open Mon-Fri 11.30am-4pm; Sat-Sun 9.30am-4pm

Botanic House, Mrs Macquarie's Road, Sydney 02 9241 2419, botanichouse.com.au