The Christmas sandwich is one of the finest traditions of the festive season – and this year offers no shortage of choice for the connoisseur.

EAT offers the Festive Full Works On Malted Wheat Baguette (£4.25). Sainsbury’s goes a little rogue with The Big Beef (£3). Starbucks has two, the slightly blasphemous Turkey, Ham & Cheese Toastie sharing the shelf with a more traditional Turkey Feast Panini (both £4.25).

Or if the above options seem a little bland, head to Japanese restaurant Tokimeitē for London's most luxurious Christmas sandwich – a limited-edition Wagyu Katsu Sando priced at a rather eye-watering £150pp. Let’s hope you made Santa’s Nice List.

According to a press release that makes you want to lick your computer screen, the Wagyu Katsu Sando “will see a premium 120g A5 Japanese wagyu beef fillet coated in panko breadcrumbs and lightly fried, before being sandwiched between fresh brioche with melted Saint-Nectaire cheese and Japanese Demi-Glace sauce. Once served, the sando will be topped with shaved white truffle at the table.”

Sometimes you have to seize the moment – so a couple of days after receiving this email, we turned up to Tokimeitē to try the thing for ourselves.

Like almost every other dish in Tokimeitē, the sandwich is prepared before your ever-widening eyes

Tokimeitē is a fine place to turn up to, with plenty to enjoy beside £150 sandwiches. Try and get a seat at the bar, where you can watch chef Daisuke Hayashi work his magic – neatly bisecting a lobster, slicing and dicing sashimi into perfectly calibrated portions to be served on a miniature ornamental garden. Even vegetarians should appreciate his artistry – albeit maybe not the lobsters’ twitching legs.

Like any good show, you need a few support acts before wheeling out the main event. A tasty miso soup with wild mushrooms gives the old taste buds a work out for the fun ahead. Better yet is the vegetable tempura, its featherlight coating of batter giving way to the flavour of the vegetable beneath. I’ve never eaten a battered anything and not felt slightly unhealthy, but the vegetable tempura might be the exception to that rule. Pro tip: mix your spring onion and radish garnish into the accompanying sauce.

Good as this food is, and it really is very good, let’s face it: we’re all here for the sandwich.

Like almost every other dish in Tokimeitē, it's prepared before your ever-widening eyes. This is Event Food, and the Event begins long before your first mouthful. Chef Hayashi lovingly submerges the slab of meat in a container of Demi-Glace sauce, then pops it onto a slice of toasted brioche. You know shit's getting serious when he starts blowtorching the cheese.

The crusts are trimmed off, the sandwich divided once horizontally and twice vertically to make six mini-sandwiches – presumably each valued at £25. Before taking your first mouthful, it’s worth inspecting the sandwich to enjoy its topography, the layering of one ingredient onto the next. Then bite into the best steak sandwich you’ll ever eat – soft yet full of flavour, the warm ressurence of comfort food mixed with the excitement of fine dining.

The VIP is the Saint-Nectaire cheese, adding a real punch of flavour – you want a £150 sandwich to come out swinging

The VIP is the Saint-Nectaire cheese, adding a real punch of flavour – you want a £150 sandwich to come out swinging – as well as a tangible tang of Christmas that might otherwise be lacking. You could imagine eating this at your grandma’s table, provided grandma has a Michelin star and access to Wagyu beef.

You could soften the financial blow by splitting the sandwich; three of the little ‘uns provide ample sustenance. However you might then start resenting your dining companion, especially if you make the mistake of finishing your half first. On the other hand, the green tea panna cotta, an art instillation of a dessert, provides a delightful palate cleanser that softens the withdrawal symptoms already setting in.

The Wagyu Katsu Sando will only be available through December, and only four will be made daily – advance bookings, needless to say, are recommended. For that matter, so is the sandwich.

For more info, see tokimeite.com