Tantra in Edinburgh is far and away the oddest restaurant I’ve been to this year. In fact, perhaps my entire restaurant career can now be divided into a time before Tantra, when life felt simple, and a time after, when all other dining experiences are merely pedestrian. Tantra describes itself as “elevated” Indian cuisine, and the front of the building has the word “PROGRESSIVE” emblazoned across it, maybe as a warning to hang on to your pants, because these guys really mean business.

It’s not an eatery or street-food joint; rather, it is “a streetery”. It’s also a cocktail bar that serves the likes of a Queen of the Dragon, brimming with Midori, Cointreau, prosecco and something called “perfume myst” that comes with a lime-flavoured replica dragon’s tail poking out of a cloud of dry ice. Tantra loves dry ice, and it never knowingly misses an opportunity to open a cloche and waft some of the stuff your way, leaving you in a mysterious fog and resembling a Hanna-Barbera villain. The Peacock Pistachio, meanwhile, turns up on a glass tripod and is garnished with “mamam” jelly and faux peacock feathers. Those are two of the more casual, everyday cocktails.

I no longer drink alcohol, but by God I wanted to, if only to force Tantra to make at least some sense. The place is as cavernous as an old-school The Hitman and Her-style “niteclub”, painted mostly black and with an interior design theme fever-dream that could be more accurately described as Funkadelic-era George Clinton. There are flashing neon blue lights, patches of plastic greenery hanging from the ceiling, paisley wallpaper and mirrored walls.

“Are you ready to order?” a server asked. “No,” is what I wanted to reply, “I shall never be truly ready, because I’m still trying to process everything I’ve seen in the last four minutes and my brain’s computer needs a full NVRAM reset. Also, your menu has approximately 68 dishes on it, and I have no idea what “Fuchka Xplosionz” or “Bone Marrow Canoes” are. Also, neither do you, because it’s your first day here, you poor thing, so let’s just go gentle into this good night together.”

We ordered a round of lassis, which came in ornate goblets and tasted like butterscotch Angel Delight, so were therefore utterly marvellous. Less modern streeteries might at this point have offered some poppadoms, but Tantra furnished us with a “crisp board … with progressive regional dips”. This turned out to be seven shards of poppadom in various colours, one of them luminous green, that were plated on blobs of pickle and raita, so some of them had gone soggy. “Tantric lamb cutlets” came next, and were so called, I think, because the chops had had a long, hard session under a hot grill and were extremely well done. Like almost everything at Tantra, they were served on a black plate with a flamboyant garnish, in this instance a roughly 30cm-long sprig of rosemary, which is about the amount of foliage you could get away with on a fascinator at Ascot.

At no point during lunch did I have a clue what was going to happen next, and I loved every second of it. These people are true mavericks. Sure, the venison sheesh wasn’t too exciting, but it came on a slab of black slate and sitting on vivid smears of beetroot glaze, all festooned with large non-edible flowers, puddles of ginger chutney and half a dozen parsley garnishes, so that was novel. The curries, on the other hand, came with far fewer bells and whistles, and were really rather good. Duck chettinad was fragrant with ground coconut and black pepper, and packed with generous slices of nicely pink duck breast. Makhani saabat maanh turned out to be dal makhani with a real kick of ghee, garlic, cream and cardamom, while the dum hyderbadi gosht biryani was light, golden and delicately spiced, and far too dainty to eat while listening to a loud remix of I’m Good by David Guetta.

The folk at Tantra really love sizzling plates, and are never happier than when they’re whizzing something past your table that might feasibly set your eyebrows on fire. All very exciting, I know, but I draw the line at the “sizzling chocolate brownie”, which was more a stale lump of cold brownie on a red-hot dish on to which the poor server was then contracted to pour boiling hot chocolate syrup. As a result, the entire plateful quickly set into an inedibly coagulated fire hazard. “We’ll have the bill now,” I said through very small lips.

We walked back to the car silently, feeling truly gastronomically elevated. The word tantra used to make me think of Sting and Trudie in their Tuscan villa, engrossed in a nine-hour lovemaking session, but from here on in, Tantra will always be this place. Once visited, never forgotten.

• Tantra 15 Castle Street, Edinburgh EH2, 0131-385 0000. Open all week, Mon-Thurs 5-11pm, Fri-Sun noon-midnight (11pm Sun). From about £35 a head à la carte, plus drinks and service

• The fourth episode in the new series of Grace Dent’s Comfort Eating podcast goes live on Tuesday 24 October. Listen to it here. Her new book of the same name is published by Guardian Faber for £20; to order a copy for £17, visit guardianbookshop.com