NEW YORK — Let’s hope a little thing like a broken engagement won’t keep Elisa Padriera away from “30 Rock.”

Salma Hayek’s spirited guest appearances as Padriera are among the best this absurdist comedy has to offer. Hayek throws herself into her role with gusto, matching Tina Fey and Alec Baldwin step for silly step, and it would be a shame if Thursday’s shot was her last.

She returns to tell Fey’s Liz Lemon that she can’t accept Jack Donaghy’s (Baldwin) engagement offer because she has a shameful secret.

“Are you a man?” Lemon asks.

“Is that your guess? You’re a man? Do you want to see me naked?” an insulted Padriera says.

Replies Lemon: “Sort of.”

No, she’s la viuda negra — the black widow — known for killing her former husband in a fit of jealous rage.

Donaghy’s willing to overlook that transgression (“everybody has a bad day”) until he sees her capacity for jealousy up close. She secretly follows him when he’s out on the town with Tracy Jordan, revealing herself at the end. Set aside for a moment the idea of Hayek going undercover in New York nightclubs — we said this was an absurdist comedy — Donaghy is spooked and calls off their engagement.

Jordan has a secret of his own, one he shamefully admits to Donaghy. In 20 years of marriage, he’s never once cheated on his wife. All those times he passed out phone numbers to ladies in the clubs, they were false numbers.