Top chef reveals why he wants customers to keep their criticisms to themselves - and why it's ok to just order tap water

Every week our Money blog interviews chefs from around the UK, hearing about their cheap food hacks and more.

Today we chat to Kray Treadwell, a Michelin Young Chef of the Year winner who owns and runs 670 Grams in Birmingham. I don't believe that all of these places that claim to be zero-waste use absolutely everything...

especially when the ingredients taste like crap, and they then try and make it into something for no reason. If it's not tasty don't use it - we have bins for a reason! I hate it when customers give criticism...

I'd rather that you simply didn't tell me at all, because without being rude, your opinion isn't going to change my views on how I should think something should be. I also really don't like it when they call me Craig when my name is Kray… But hate is a very strong word as I love all of my customers.

The worst type of behaviour in kitchens is... poor timekeeping and uniform.

I think they're very important and get overlooked. Being five minutes late is still late and coming to work and not being presentable is not acceptable.

If you work in Boots, House of Fraser, Selfridges or a hair salon, there's a standard that you need to meet to work each day and my view is that there are standards that need to be met in a kitchen. It says quite a bit about who you are and what you're about.

The most overrated single food item is… sea urchins. They're not that unpleasant in taste, though they do have a bit of an iron aftertaste.

For the price, the preparation involved and what you actually get to use from one for me means there's no real point in using it as an ingredient. The best chef in the UK right now is… Adam Smith at Woven.

I think his cooking takes you back in time - how it should be done but obviously with elegance and a modern twist like no other. The restaurant is unbelievable, and on top of that, he's an incredible person inside and out.

Read more:Top chef picks favourite chain restaurant - and shares 'ultimate' late night cheap eat'It's overrated': Top chef on expensive food item that isn't worth itChef reveals his pet hate from customers and cheaper olive oil substitute One cheap place I love where I live is... called Yikouchi at Chancers Café in Stirchley.

Stirchley's got a massive food and drink scene at the moment, with The Rabbit, Couch, Deadbeat and Eat Vietnam. Yikouchi is run by a chef who used to live in China, he just cooks gaifan, which means topped rice, so you can go in and have a pork curry with rice for £10 or smacked cucumber for £5.

It's also home to some of the best fried chicken around - other than mine that is! My view on customers just ordering tap water is that... everyone's circumstances are different, and you should feel lucky that customers are coming to your restaurant.

There's a happy medium, like there is with most things. If you're at a table of six on a Saturday night in a 20-cover restaurant then maybe try not to order tap water to drink but perhaps instead maybe consider going on a Wednesday instead.

But the reality is that you're entitled to drink what you want and also entitled to dine wherever you want. The best city in the world to eat is...

Barcelona. The city's food has always been what I've found to be the most interesting, not just fine dining but the little tapas bars in quiet side streets.

I love that sort of food where you can just eat lots of little bits, olives, tomato bread, jamon, croquetas, devilled eggs, fried whitebait, stuffed padron peppers, octopus etc. I just love that sharing element of food - it's really special.

One ingredient you should never skimp on is… caviar. If you're going to serve it - serve more, so people can appreciate it for what it is.

When I ate at Woven a couple of weeks ago, Adam and his team kept coming with more and that's the way to do it in my view. It's a luxury ingredient that just gets better the more you taste it - so always serve more.

My favourite restaurant chain is... McDonald's.

My son wouldn't be alive without it because all he eats is chicken nuggets with BBQ dip. But please don't judge - he has autism, and as a result, there aren't many foods he will actually eat..