Traders are cashing in on the Marmite crisis, asking as much as $800 for a jar of the black gold on Trade Me.
Manufacturer Sanitarium has warned New Zealand's Marmite stock is expected to run out within weeks.
The company has suspended production until July after earthquake damage to a cooling tower at the company's Christchurch factory rendered the nearby Marmite building unsafe.
News of Marmite's temporary demise has spread through social networking sites such as Facebook and Twitter like hot butter on toast, with "Marmite" and "Marmageddon" trending nationwide. Already established Facebook pages - both pro and anti Marmite - attracting thousands more followers.
Even Prime Minister John Key, down to his last jar at the Beehive, is not immune.
On Trade Me, dozens of auctions popped up, for both new and used jars of Marmite.
One seller in Hamilton had a buy-now listing of $800 for an unopened 250g jar. The auction had not gained any bids this morning, but had attracted a number of questions.
Another listing, urging bidders not to "settle for someone's half eaten butter stained Marmite" had received four bids this morning, and was sitting at about $10 for two unopened 250g jars. The reserve however had not been met at 8am.
Countdown's online store is now only selling 250g pots of Marmite at $4.25.
British expats living in New Zealand have been warned they may have to hunt for the original English version, or "as a last resort" they may have to switch to Australia's Kraft version of the yeast extract spread - Vegemite.
The Prime Minister told TV3's Firstline programme he had to follow Sanitarium's advice to spread thinly "only on toast".
"I only have got a very small amount in my office and once that runs out I'm aware supplies are very short," he said.
But in a confession perhaps showing Key's centrist tendencies, he admitted he can also eat Marmite's rival, Vegemite.
"I am a consumer who can move between brands. I'm ashamed to say it, but I can eat both."
Sanitarium general manager Pierre van Heerden yesterday recommended enjoying the spread on toast, not bread, as the heat would melt the Marmite and stretch it further.
Polling on Marmite rationing also opened yesterday, with iPredict offering punters $1 for the correct guess on whether either Foodstuffs or Progressive Enterprises place restrictions on the number of jars a customer can buy before August 1.
Progressive Enterprises, which owns Countdown, confirmed yesterday they would not start rationing, but expected to run out of stock in all its supermarkets within two weeks.
The Christchurch plant produces about 640,000kg of Marmite every year.
Which memorial design do you like most?Related story: Christchurch earthquake memorial designs unveiled