Queens district attorney candidate Tiffany Cabán couldn’t cut the mustard Tuesday in her effort to invalidate ballots cast against Borough President Melinda Katz.

Jerry Goldfeder, the lawyer for public defender Cabán , in attempting to dispute votes in the tight Democratic primary race that saw Katz entering Tuesday with a slim 60-vote lead, sought to show that a yellow stain on a ballot for the borough president was more likely caused by a yellow highlighter pen than the some French’s yellow.

The pale mark, the contest’s version of the 2000 presidential election’s hanging chad, would invalidate the ballot if it were made by a yellow marker or some other writing implement, but not if it were merely a food stain.

John Ingram, the Brooklyn judge overseeing the challenges for the Queens Board of Elections, questioned whether the smear was “French’s or Gulden’s” as he tried to slather some levity on the tense proceeding.

“The mustard stain does count,” he ultimately declared in the ruling for Katz.

Goldfeder accepted the decision — albeit without relish — adding that he’s come across other ballots splattered by hamburger, ketchup and pizza.

Katz headed into the hearing leading Cabán by 60 votes, but the public defender was able to trim five votes off the lead before all sides broke for the day. The ballot challenges will continue Wednesday morning in Queens Supreme Court.

During a lunch break, Goldfeder clarified for a reporter why he attempted to beat the spread, as it were.

“We thought it was a marking. We thought it was a highlighter, a yellow highlighter,” he said. “It turns out to be mustard and ballots should not be invalidated because of the food stains.”

Last Monday, the New York City Board of Elections certified Katz as the winner with 34,920 votes, a razor-thin edge over Cabán’s 34,860.

But Cabán is arguing the BOE improperly excluded “hundreds” of ballots that could once again tip the scales in her favor.

Following the hearing, Goldfeder fled before reporters could ask whether he believes Cabán still has a shot.

However, Katz campaign adviser Matthew Rey claimed “there is absolutely no math that would overturn Melinda’s lead” and that “it is now time to allow Queens to move on in order to begin working on crucial reforms to the District Attorney’s office.”

The winner of the Democratic contest will become the heavy favorite to win the job in the November general election in the increasingly left-leaning borough.