Olive Garden tried — and failed — to cure its customers’ craving for all-you-can-eat deals.

Shares of the red-sauce mecca’s owner, Darden Restaurants, tumbled 5 percent Thursday after it revealed sputtering sales in the most recent quarter were only revived because it reintroduced its “Never Ending Pasta Bowl.”

Comparable sales across Olive Garden’s 900 eateries nationwide rose 1.5 percent — their skimpiest increase in two years — and likely would have dropped if management hadn’t begun dangling discounts in late September for the nine-week promotion, officials admitted.

“Olive Garden had a difficult promotional start to the quarter,” Darden chief executive Gene Lee said on a Thursday earnings call. But “Sales improved as we moved into Never Ending Pasta Bowl.”

The chain’s sales in the first month of the quarter ended Nov. 24 were negative until it began the discounts, said Lee, adding that price-sensitive customers “will go somewhere else” if they don’t see an attractive “offer.”

The Never Ending Pasta Bowl, which costs $10.99 at Olive Garden’s Big Apple locations, lets diners refill their plates with as much pasta and sauce as they want.

“Olive Garden felt that it could roll back on the promotional cadence now because the economy is doing well,” Wedbush analyst Nick Setyan told The Post. “They tried and then reverted back to discounting.”