Swiss Butter - Best London Steak under £20?

🇨🇭Could this be one of London’s best steak dinner under £20? There are always long queues at @swissbutter for people trying to get a taste of that steak and chips with special sauce.
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🥩There are only three things on the menu (beef, chicken or salmon) and each is served with salad, chips and baguette. We went for the beef cooked rare, and it was very well cooked. That secret sauce is where it all comes together though - wow! Buttery with a hint of mustard, it was the perfect partner for the steak. We found ourselves soaking up that sauce in any way we could with the chips and baguette.
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*PR Invite
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📍Holborn
💷 £19 steak and chips; £9-10 desserts