This is one first class hero.

A New Jersey granny with a big heart recently went viral for making a salami and cheese sandwich for her mailman — who thought it was the best thing since sliced bread.

Antoinette Giancamilli, better known as Nonna Netta, has a tradition of presenting her postman, Kyle Frankenfield, with homemade food when he delivers the mail to her Alpha, NJ home, just east of the Pennsylvania border.

“It started out when I was roasting chicken and I gave him a chicken leg,” Giancamilli, 83, told The Post.

“Sometimes I just give him scones or a muffin or a piece of pizza. Whatever I have, I give him … But he loves a bagel with salami and cheese, that’s his favorite.”

The viral clip, which got close to 9 million combined views, started with the octogenarian in her kitchen, putting together the Genoa salami and provolone cheese on a bagel and toasting it.

“Got a sandwich for you, Kyle,” Giancamilli announces when she sees him approaching.

“This is like the third time this week,” the grateful mailman answers incredulously.

Once she hands him the sandwich, he gushes, “Anything you ever make is the best thing I’ve ever had. Thank you so much. You’re like a third grandmother to me.”

After the sandwich became so popular online, Giancamilli started to share it with other visitors.

“The guy just came to change our water heater tank and I said, ‘Do you want the mailman special?’ and I gave it to him too,” she said.

The mom of four and grandma of nine has more than 2 million combined followers on social media thanks to her grandson, Luke Hardin.

The idea to share his nonna, which means “grandmother” in Italian, with the world came in 2023 when he would visit her for lunch during his summer internship and post photos of the meals she would make him on TikTok.

“It would be a steak sandwich, hamburgers,” Giancamilli said. “And people commented, ‘Boy, I wish I had a grandma like that.'”

Now, the native of Rome, who immigrated to New Jersey in 1956 at 14 and started working as a seamstress for 75 cents an hour at 16, cannot leave the house without being recognized.

“Every time she goes to the grocery store, there’s at least a couple people that she doesn’t know that recognize her,” Hardin, 24, said.

“Even all my neighbors, they all know me,” Giancamilli added. “They say, ‘I watch you all the time, especially when I’m hungry.'”

The beloved nonna’s most popular videos have been the one of her roasting tomatoes for sauce, which racked up 110 million views, making cinnamon buns, which garnered 95 million, and whipping up pasta with pesto and shrimp, which got more than 21 million.

Her recipes are in such high demand that she’s even releasing a cookbook.

“She’s really seeing the impact that she’s having, all these people saying that they cooked cutlets for the first time or made pizza with their family,” Hardin said.

The spry senior, who is celebrating her 70th anniversary of moving to America next month, cooks for her family of 20 every Sunday.

“She has a saying, ‘If you feed them, they will come,'” Hardin said.