EVER since Secret Service heard about a restaurant that cooks steak on searing hot volcanic rocks right in front of its diners, we've been keen to try it out.

And after a few weeks of trying to book a table, your spy and a companion managed to bag a spot at The Black Rock Grill and see what all the fuss is about.

The black rock plates that the eatery takes its name from are heated to a super hot 440 degrees, allowing the meat to instantly sear and hold in all the proteins and juices as it cooks.

The whole idea is that you can decide how long you want that steak to stay on the heat for and whip it off when you can't resist the temptation any longer.

Black Rock Grill is situated above Sadlergates, a bustling café at the bottom of, you guessed it, Sadler Gate.

It's a pleasant, attractive setting in a 200-year-old building, which was given a tasteful and minimalist £200,000 overhaul last year.

The first thing Secret Service and our fellow spy noticed about the menu was that it wasn't massively extensive – although everything on it certainly sounded of the highest quality.

Black Rock Grill proudly declares that all of its beef steaks are 8oz and sourced locally from farms around Derbyshire.

That certainly sold it for your spy and our companion who, despite a couple of vegetarian options, decided to plump for steaks.

Starters are priced between £4 and £6 but we decided to skip them and get to the main event.

Your spy ordered a fillet steak while our fellow diner went for the sirloin, both of which were served with salad and a handful of chunky homemade chips.

We also decided to turn our dishes into surf and turf by adding black tiger prawns at a cost of £3.50 each.

At Black Rock Grill, once the side dishes are ready, the steak is quickly seared on both sides by the chef and then brought to your table, sizzling on the volcanic rock in the middle of your plate.

It's a wonderful sight, making for a nice break from the norm and definitely a conversation piece.

Your spy decided to sample the Derbyshire steak rare so it wasn't long before we were cutting into the sizzling meat.

It was definitely of a superior quality and, because the juices were locked in, it was succulent and juicy from the first bite to the last. We shared a mushroom sauce that was very rich and creamy and obviously homemade, as were the chunky, crispy chips.

The best part about the steak was that, thanks to the heated rock, it was still piping hot at the last bite.

Your spy's only gripe was the black tiger prawns. Although they looked impressive, for £3.50 each we expected more than three fairly small ones and they tasted dense and a little mushy.

There is a small selection of homemade desserts but we were just too stuffed and enjoying the taste of the steaks far too much to sample them.

There is also, for the more adventurous diner, an Australian Outback menu including kangaroo rump and water buffalo.

Overall, Black Rock Grill made for a very enojoyable and atmospheric night, with friendly service and a touch of the theatrics complementing some fantastic food.

WHAT: Black Rock Grill, Sadler Gate, Derby

MEAL FOR TWO: Fillet steak, £18.95, sirloin steak, £15.95, two portions of black tiger prawns, £3.50 each, mushroom sauce, £1.50. Two soft drinks, 90p each, one bottle of water, £3.50.

TOTAL: £48.70

BOOK: Call 01332 368822 or visit www.sadlergates.