Imagine Sydney remapped as bright, intersecting blocks of reds, blues and yellows – Crown, Foveaux and Riley streets splicing into each other like in a Mondrian painting. This is what you see on entering District Dining in Surry Hills, and it’s a sign of the spectacle that will appear on your table.

Like the bird’s-eye city perspective at the bistro’s entrance, you’ll need an aerial view to take in each dish that arrives – sculptural scoops of yogurt, an installation of olive bread slices propped against stick-thin haloumi and heirloom tomato quarters.

Unlike the featured mural, the food doesn’t stick to Mondrian’s minimal three-colour spectrum – instead, it bursts through with bright and blushing shades – a swoop of harissa green here, or a burnt-sunset wedge of pumpkin there.

District Dining is a new venture for Warren Turnbull, head chef and owner of two-hatted Assiette. It’s meant to be a touch more casual, and it manages to feel more relaxed (without being overfriendly or sloppy) while staying sophisticated. It’s really likeable.

I’m going to admit, the first fine-dining restaurant I ever went to was Assiette in 2005, and I revisited it again in 2007. The food, in both cases, was exceptional – I wanted to snap-freeze the memory of every thing I ate on both occasions, especially the Mille Feuille of Passionfruit Cream and Tropical Fruit Salad and the Lime Panna Cotta with Orange Sherbert and Orange Caviar. The only cold note was the service, which was noticeably frosty on both occasions, and in fact, it left me assuming all waiters had a default-snooty attitude to young diners – until I went to places like Bentley and Oscillate Wildly, where the service is so inviting and un-judgmental about your bank balance. As much as I liked the food at Assiette, the wait staff left me feeling like we weren’t quite as welcome as, say, investment bankers. So I’m happy to note that District Dining hasn’t inherited this attitude – the service is much warmer and friendlier.

And the food, too, is high-grade – each dish has a touch of magic (without the buzz-killing pricetag that can accompany this quality of dining). There are mains – such as the Hopkins River Sirloin, teamed with a lively smear of green harissa and a small copperpot of kipfler potatoes, all fat-glossed and cooked through with caramelised onions ($24) – and plates to share. There’s a dish of gold and purple-bright Beetroot, served with sumac-sprinkled clouds of salted yogurt and gorgeously roasted nuts ($14). There’s also Spiced Pumpkin with marinated feta ($14), and, because there aren’t many vegetarian options*, I have the Heirloom Tomato Salad without the mojama ($16), which is fine, as the the gold-crunch haloumi, toasted thin slices of olive bread and full-flavoured heirloom tomatoes are enough to keep me happy. Besides, from the first menu glance, I was really staking out for dessert.

Will claimed the Coffee Brulee with Chocolate Madeleine ($12), and after much sizing up of the remaining options – the equally dreamy sounding Buttermilk Panna Cotta with Blood Orange and Granita ($12), Meringue with Strawberries, Raspberries and Cream ($12) and Efi’s Rice Pudding with Cinnamon Ice Cream ($12) – I went with the meringue thanks to the advice of our good waiter, Lindsay (who also multi-tasks as restaurant manager, sommelier and inhouse Twitter expert – by the end of our lunch, chef/owner Warren Turnbull was ready to dispense 140-word updates on District Dining.)

The meringue is completely endorsement-worthy – Lindsay is right. It’s a wonderful take on Eton mess; a gorgeous scoop of raspberry sorbet crowns strawberries, cream, sweet ripples of fruit and surprise chunks of meringue. A new favourite dessert.

The design of District Dining is also an achievement – only six weeks ago, it was a gaming lounge (designed by Burley Katon Halliday!); its high-speed transformation into a welcoming, wood-panelled space is something of a wonder.

When Will and I had lunch there today, we really had the entire place to ourselves. It’s a temporary luxury, we know, because District Dining only opened earlier this week and, for now, has stayed a scaled-down secret. The place will undoubtedly crowd up quickly, because a bistro with a likeable menu, good prices, breezy atmosphere and a location only footsteps away from Central Station (or, more dangerously, a well-known karaoke joint) is not going to stay unknown for long in Sydney.

*If you ask, the chef may be able to offer other off-menu vegetarian options

17 Randle Street, Surry Hills, Sydney, NSW (02) 9211 7798, www.districtdining.com.au