WHAT is a hidden gem? Do they really exist? And if they do, can they be hidden in plain sight?

Answers coming up, as we review Thira – which has the potential to be hailed as a bona fide Blackburn hidden gem – that is if we decide, if it’s hidden, if it’s a gem, and if hidden gems are really a thing.

Tucked away for all to see on Darwen Street, next to Radio Lancs and opposite the Postal Order, you might struggle to argue that Thira is hidden.

But it is so unassuming, and so devoid of bustle, that it is quite easy to walk past without even a second glance.

We were the only ones there the lunchtime we visited. But then it was a Monday.

This Is Lancashire:

Keen to curry favour with my workmates (see what I did there?), I invited the gang down to join me for lunch, and they duly obliged, keen for a free feed on Mystery Diner's ever-expanding expense account. (The only thing expanding faster is is his waistline – Ed.)

My curiosity had been piqued after noting Thira's number one rating on TripAdvisor. So why has no one heard of it? Whenever mentioned to anyone I quizzed about this place, I got blank looks and shrugs.

What is going on? How is this place flying so high, yet staying under the radar?

The starters were a clear marker that this place means business.

As well as the obligatory poppadoms, we ordered medu vada – deep-fried mashed white lentil doughnuts with a coconut chutney – and the slightly less exotic clay oven baked chicken tikka, with yoghurt and spices.

The chicken was fine, but the the medu vada could sit on the table of any fine dining restaurant – but just as equally be served up for a fiver a pop from a trendy street food van. Vegetarian too, and possibly vegan, but don't quote me on that.

This Is Lancashire:

The mains are a delight at lunch, and superb value too. For £6 you get a delicate curry (lamb, chicken, veg, or fish) rice, dhal, chapati, a side dish and a dessert.

The food here is all good, but it is the attention to detail on the presentation which earns Thira brownie points.

I had a masala dosa – again veggie. Brilliant stuff. Basically, it’s pancake, filled with Bombay potatoes, but it’s a lot better than that. Balanced flavour, and light-ish on the belly, despite containing a week’s worth of carbs. Easy on the eye too. Top marks for looks, once again.

The other dish worth a mention is the Kerala fish curry. It was a delicate delight. The tomato-tang of the curry was perfectly offset by a good hint of chili, and the white fish was soft and tasty.

The star of the show though was a homemade paratha to mop up the sauce – an Indian flatbread much lighter than a naan but more substantial than a chapati.

This Is Lancashire:

The dessert came in the form of a cracking, cold rice pud, just like granny used to make, but without the skin or the stodge.

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Thira is licensed, but it was Monday lunchtime, and journos just don’t drink on the job anymore – well, not on a Monday lunchtime anyway – so four hungry hacks were fed and watered for just under £40 at this not-so-hidden gem.

Thira is a humble family run establishment and they clearly have a talented chef. It is easy to see how this restaurant has gained top marks online. It certainly gets five stars from me.