Walking into The Delaunay is rather like entering a jazz bar from the Golden Age. The restaurant oozes with elegance, sophistication, and with its low lighting, mysterious seduction.

Its art-deco inspired interior is complemented by its colour scheme of emerald green and black, and the use of wood and mirrors throughout, which along with the abundance of silverware, are responsible for creating its decadent feel.

Newly launched as the sister restaurant to The Wolseley, The Delaunay is taking a fresh approach to European dinning. Where The Wolseley has moved towards French territory in terms of cuisine, The Delaunay wants to focus on a more Central and Eastern European experience, as is evident from the ‘Wieners’ and ‘Schnitzels’ sections on the menu.

Sitting down at 6.30pm, I watched with interest as the bar and tables around us welcomed a steady stream of rather eclectic clientele. We were talked through the menu by our waiter and on his recommendation my dinner date went with the Winter Beetroots and Honeyed Goats’ Curd Salad, while I chose the beautifully crispy and creamy Tarte Flambée with smoked bacon and shallots, which you could easily share among two. Both were delicious, but I must admit that I was rather envious of the soft and creamy goats curd staring at me from across the table.

Moving onto mains and we indulged in the juicy Rib Eye Steak, which was accompanied by a delectable béarnaise sauce and a rather large portion of perfectly thin and crispy french fries. To offset our guilt we added some wilted spinach. Accompanying it was a bottle of the Rioja Reserva 2005 Marqués de Murrieta, although it’s worth noting that along with the wine, cocktails and champagne, The Delaunay also has a specialised Reserve wine list too.

After thinking that I couldn’t possibly have room for any more food I heard myself ordering dessert...their raspberry ice-cream was a refreshing alternative to strawberry and the perfect way to end the meal.

What sets The Delaunay apart from its competitors it that it’s open 7am to midnight. While there are set dining times, it runs a continuous stream so that breakfast rolls into brunch, brunch into lunch, lunch into afternoon tea and so it goes on.

The service was impeccable and the smartly turned out staff extremely friendly; one gets the impression that they enjoy talking to their guests rather than feeling obliged to. The detail and ambience of the place was wonderful, and so swept up by it all were we that as we rose from our table we realised that we had been there for three hours – this is just the place for those long, Mad Men-esque lunches!

Opening hours: The Delaunay is open from 7am until midnight Monday to Friday, 8am to midnight Saturdays, and 11am to 11pm on Sundays.

Although booking is advisable, the management will be reserving a number of tables for walk-ins, so if you pop by on whim you may find yourself lucky.

Emma Westman is a freelance travel writer based in London and has lived in Edinburgh and California