The way to tell a good Tambrahm from an average one is to test her knowledge of mananthakali. The better of the species would have, at some point, had mananthakali chips - fried, crushed with some hot rice and ghee, swallowed in minutes. For this berry has that thing about it.

It's commonly available as mananthakalivettal (chips) in small packets of 100 gm (priced at around Rs 40) in most shops that stock South Indian goodies like banana chips, tapioca chips and Madras onions. The chips - marinated, dried and dehydrated mananthakali berries - are nothing to look at. They are muddy brown in colour and have the peculiar smell of dahi marinade. The taste, when acquired, is exciting.

For my father, a mild flirtation with the berry - it grows in our garden - is now a full blown affair. He wants to show the world the infinite possibilities of this innocuous green berry (which turns purple and black on ripening) yielded by a weed, a herb with small white flowers that's commonly known as gurukkamal, kakamachi or black night shade and grows in dry parts of India.

He computed that at 40 rupees a packet for the chips, there was money to be made. Off he went on a mananthakali adventure to Belgaum. On a friend's plot of land, Dad grew berries from seeds he obtained from drying ripe berries. Soon, bagfuls of the berries arrived and the marinating began. The whole house stank of berries in curd. Sleeping in their stench became impossible. But my dad plodded on, till they were dried and harvested. He weighed each sachet of chips, calculating how quickly he would be a millionaire.

Things backfired once. One lady came back with the chips, flung them at us, and narrated the tale of how the oil scalded her face when she was frying them. My father just managed an "Oh, maybe it wasn't dried enough. " From then on, the marinated berries were dried for two weeks in the hot sun before they were packaged.

More uses were found for the plant in the meanwhile. The leaves began to find their way into sambars, daals and sabzis (used like palak or methi leaves). The leaves and berries, both raw and ripe, were used in pachadi, a condiment.

The mananthakali disease was contagious. Once my mother and I checked into a railway retiring room in Mysore. When she went missing for a few hours, I set about searching for her. She was in the railway yard, in a thicket of bushes, plucking mananthakalis furiously from some weeds. Unfortunately, the berries didn't make it to Bombay. They had all rotted on the way. My mother was crestfallen.

Things have quietened on the berry front at our house. My father never got rich, but he is still loyal to the mananthakali. A plant continues to thrive outside our window, bearing fruit and leaves, and enticing my parents to continue their mananthakali experiments from time to time.

Available at Vinayagar Stores and Murugan Stores in Matunga and Muthu laxmi Stores in Andheri (W) in Mumbai