Entertainment

A bunch of munch!

Richard Belzer has a lot on his plate. When he’s not busy cynically tracking down bad guys on “Law & Order: Special Victims Unit,” the stand-up comedian is rounding up musical impressions, celeb interviews and conspiracy theories. His new book, “Hit List: An In-Depth Investigation into the Mysterious Deaths of Witnesses to the JFK Assassination,” is out April 15. And in a return to his pre-badge stand-up days, he’s staging Richard Belzer’s Rock & Roll Comedy Extravaganza on Saturday at Stage 72 at The Triad on West 72nd Street.

The Post caught up with Belzer on his way to the Friars Club to prep for a roast of Jack Black.

You’ve been playing Detective John Munch, both on “Law & Order: SVU” and “Homicide: Life on the Street,” for 20 years. How much longer can you stick with one role?

Presently I am the longest running character in the history of primetime television. You know, the part is a gift from God. To be able to work for 20 years as an actor in an industry that is not so predictable, I’m grateful every day. I’ll do it till I drop, I guess — or drop out.

You just got back from your home in France. Do people recognize you there?

Yes, our show is a big hit there. They call it “New York, Unité Spéciale.” And they call me Inspector Munch.

What’s this Rock & Roll Comedy Extravaganza about?

It’s a homecoming for me because I live in the neighborhood [the Upper West Side] and I haven’t performed in a long time, so there’s a lot of good vibes. My band and I do parodies and impressions in addition to classics and comedy, which I suppose are my roots.

As a result of being on “SUV” and “Homicide” all these years, there’s a lot of people who don’t know I used to do stand-up. When they see me onstage, it’s a surprise and it’s revelatory. I’m happy because I can do my old material, so everybody wins.

What impressions will you be doing?

Springsteen, Jagger, Dylan, Leonard Cohen and many other surprises.

Have you ever met any of the stars you impersonate?

One night I was doing Mick Jagger and I didn’t know he was in the audience — that was in the ’70s. So I went backstage and the owner of the club said, “Mick Jagger wants to meet you.” And I was like, “Humana humana.” I went out and sat with him and we just hit it off. He was really gracious and ever since then we’ve had that connection.

And I did I Leonard Cohen for Leonard Cohen at the Rock and Roll Hall of Fame dinner. He nodded sagely and said [deep voice], “That’s good.” He’s one of my all-time heroes, so I was flattered.

“Hit List” joins the ranks of your other books examining the deaths of JFK, Marilyn Monroe, etc. What sparked your interest in conspiracies?

Being a kind of amateur historian, interested in America’s recent path from WWI on, I’ve always been fascinated by it. I feel compelled to write about it and take advantage of my celebrity — he said modestly with a knowing grin. Add that “grin” detail to your story.

We’re talking on the phone.

Tell your editor we’re on Skype. I like your skirt, by the way. Actually, I know you’re wearing pants — you’re a journalist. Now ask me what I’m wearing.

What are you wearing?

I’m wearing a black Chanel cocktail dress, the classic one she did in ’64.

Speaking of informative, you host an interview show called “Richard Belzer’s Conversation” on YouTube. Who have you had on so far?

We just had Paul Schaffer, who is really good. Dick Cavett, Gilbert [Gottfried], Ice-T — I mean, I’m only picking people I like. I enjoy it because the conversations are 20 minutes or so and nobody’s really plugging anything, we’re just having a good time. I don’t care if one American watches. If a billion and one Chinese like it, I’m in — it’s all about the numbers. I wish I were kidding.

You’re roasting Jack Black this weekend at the Friars Club. What are you going to say?

It’ll be scatology for charity. Roasts are always great because they’re not televised, so we get to see and hear some down-and-dirty, really funny stuff and it all goes to charity. I don’t know what I’m going to say yet. Who’s Jack Black again? He does all those “Hangover” movies, right?

You’re often called an “acerbic wit.” Do you mind that description?

What are you, a f – – kin’ wise guy? F – – k you! The thing is, at times I can be. And you know, I’m frustrated with a lot of things in this country, so I rant and rave. I love America, and I’m disappointed in some things — an impatience for ignorance.

The number one job for me is to make people laugh. If I can also make people think, then that’s a cool thing. That’s a modest way of saying I am all of those things. I’m giving you subtext for your interview.

Anything else you want to add in here?

There’s a lot of children that go to bed every night hungry in New York City, and it’s shameful. That’s really disturbing to me. I’m serious.