Take traditional English afternoon tea
Feeling incredibly affluent after spending a day eating delicate sandwiches and drinking tea is a traditional English luxury. Visit Claridge's or the Ritz for a more traditional experience, or in the summer, check out the terrace at The Goring or the grand Orangery. Since seats might fill up quickly on weekends and during the busy season, pre-registration is strongly advised.
A cafe with a very discreet, understated vibe but is located in a highly public area (the West End) is recommended for a "cuppa," as it is often known in the UK. Since it doesn't appear anything like a cafe from the outside, you could almost walk right by Cafe In The Crypt! The glass cylinder front resembles the entrance to a posh public restroom more than anything. But once inside, you'll see that this is a specially constructed cafe unlike most others in the city. The cafe contains real tombstones, but hopefully they won't make you turn away from the food and beverages.