This is a London food story of the big and the small, the high and the shy, a tale of multi-storey and one-storey. Let’s start at the top…well, almost at the top.

Sushisamba sits three-quarters of the way up Heron Tower, the third tallest building in the capital, near Liverpool Street Station in the City of London. It offers Japanese/Brazilian/Peruvian food in a setting that seems to be trying to redefine the word ‘cool’. The photo of the outside bar on the home page gives you just an indication of this. And if the views out over the city and out to Canary Wharf are stunning, the food looks pretty amazing as well.

For example, the green bean tempura, which costs £12. The samba salad – baby spinach, grilled kabocha, truffle ponzu, shavings of heritage carrot, radish, apple and mango dressing – is fabulous, too. That’s £15. Everything on the menu is rounded to the pound, which partly explains why a medium-sized portion of salt and pepper squid also costs £12. (But why round it? It’s not as if most people are going to be paying in cash and that some de facto no-change policy is going to speed up matters.) Kobe beef is a popular item on the menu as well, even if for my taste it’s rather fatty – and I’m not only referring to the price. However, I would concede that the kobe slider with horseradish mayo is a fine little burger.

What is undeniably great is the atmosphere. You constantly feel as if a glamorous party is about to break out. And while the food is excellent, if sometimes on the expensive side, the cocktails are apparently amazing. I’ll have to take the word of others for that. Cocktails aren’t really my thing – I’m absolutely not anti-alcohol but I prefer to have an idea of just how alcoholic my beverage is before embarking on it.

People travel to enjoy Sushisamba from all over the place, which is where you’ll probably be after an excess of those cocktails, and they come from all over London – goodness, even from south of the river! – to eat at Sunday. Now this place could not be trying to be less cool (unless the door is open because it’s warm outside). It’s a ground-floor restaurant with a small garden area at the back in an unremarkable residential road in North London.

Chorizo, fried egg and avocado served on grilled cornbread: excellent fare at Sunday for a Thursday lunch

It serves breakfast from 8.30 on weekdays, from 9 at weekends. Lunch is served from 11 until about 5 but the restaurant no longer does dinner. No wonder. With queues out of the door and down the road, even in winter, its brunch business is brisker than a chilly morning. The staff need to get their rest at some point.

What it calls “full breakfast” consists of eggs and sourdough toast, sausage, bacon, mushrooms, black pudding, baked bean and sautée potatoes. That sound pretty full-on to me. As the saying kind of goes, breakfast means breakfast and they’re going to make a success of it. And they do. That costs 11 quid. (And, no, the Sushisamaba pricing policy is not in play here. There, BTW, the Kobe English Breakfast, a “small plate” of kobe sausage and bacon, egg, asparagus and mustard, will set you back £23.) For lunch at Sunday one weekday recently my wife had courgette fritters, halloumi, avocado, poached egg and yoghurt. A bargain at £10.50. I went for the grilled cornbread, chorizo, fried eggs and avocado with corn salsa. That was…hold on, also £11. Anyhow, you can see that it looks good enough to eat. And it was.