Swiss Butter restaurant with secret sauce opens in Holborn

After debuting the concept in Lebanon in 2017, Swiss Butter has taken off in Saudi Arabia and UAE, with plans afoot to open a string of UK eateries - expanding to 100 stores worldwide in the next five years.

As the Holborn restaurant prepares to welcome punters, we went along for a sneak preview of the 33-ingredient sauce to discover will it catch on here?Swiss Butter opens its first UK restaurant this month in Holborn (Image: Swiss Butter)

The setting is casual dining - think industrial exposed brick and pipework, corrugated iron, and wood and steel furniture - and the menu is incredibly simple with mains served on a wooden trencher loaded with crispy fries (or baked potato) dressed salad leaves, slices of baguette, and a handy pinch of chili flakes.

Bar of Swiss Butter restaurant Holborn (Image: Courtesy of Swiss Butter)

All mains are priced at £19, and the only decision you have to make is whether to smother beef fillet, salmon or chicken breast in that sauce.

Invented by a Lebanese chef after multiple trial and error, it has 33 herbs and spices and an inquiry into allergens reveals 'fish derivative' (anchovies?) mustard, pepper, and of course dairy.

Despite the name, it's not buttery or greasy, but has a herby, slightly sour, peppery tang that went brilliantly with perfectly-seared firm salmon.

The main menu choice is whether to have the special sauce with chicken, beef fillet or salmon (Image: Courtesy of Swiss Butter)

We couldn't resist seeing how the sauce fared with the signature beef fillet - a cut known for its tenderness rather than flavour. Our medium rare steak was once again expertly executed and the sauce went well with it. All three options are simply cooked with just oil and seasoning, so if like me you prefer a shade more mustard and pepper on your steak, you can order the wonder sauce on the side, and apply condiments to the seared meat yourself.

Founder and CEO Eddy Massaad has pledged to expand without resorting to franchises to retain quality control, and based on our visit, he's achieved his aim with impeccable service and quality ingredients.

Interior of Swiss Butter Holborn (Image: Swiss Butter)

The bar serves beers on tap, or house wine by the carafe or bottle - I enjoyed a perfectly decent house white, but a word of warning about the desserts.

Both the chocolate fondant and custardy, caramel-laced 'pain perdu' come with dollops of ice-cream, and are the most moreish spoon-dipping puddings you will try this side of the river. They are meant to be shared, so if you go the full Swiss Butter, mop up the sauce with the baguette, then dive into a whole dessert, you might not be able to haul yourself home along High Holborn.

Beware the dangerously addictive large desserts at Swiss Butter (Image: Swiss Butter)

Swiss Butter opens later this month at 114-118 Southampton Row, Holborn, London.