Great Barrington — The bulk of Josh Irwin’s menu at Cantina 229 revolves around food that is Berkshire-grown — from carrots and kale to chicken thighs and grass-fed beef patties and a panoply of produce in between. In fact, it is the very fruits of his neighbors’ labor that fill the plates at his wildly popular restaurant in New Marlborough. Irwin’s philosophy is simple: “The more money we can spend with local farmers [the better]; it makes us feel good, the quality is going to be up to standard, and we [are able] to highlight the farmers [we support] to make sure that credit is given where it’s due.” Irwin is but one of more than two dozen Berkshire Grown member chefs and local beverage producers who will be on hand at Ski Butternut Monday evening September 23 to celebrate Berkshire Grown’s 21st annual Harvest Supper, an event that puts local food at the center of attention. As to what Irwin will be preparing? He has absolutely no idea — and that excites him.

“The entire menu is based solely on what [my local farmers] have available and what they would like us to use,” Irwin explained. “It’s all very in-the-moment,” he added of a process that involves equal parts planning and elasticity. A second rotation of cucumbers was Max Morningstar’s best guess as to what will be ready come Sept. 18, but only nature knows for sure. “If I committed to making something two months ago and then either didn’t like the quality or the weather shifted a bit and it got colder and all of a sudden those cucumbers were a lot sweeter, now the whole [menu] needs to change,” Irwin explained. It’s a way of thinking — and eating — that celebrates the abundance of what’s in season, a concept at the very core of Berkshire Grown.

“Berkshire Grown’s Harvest Supper is a signature event in our food-loving community,” said executive director Margaret Moulton. “The fresh, seasonal food is delicious, and it connects us directly to our local farms and restaurants by bringing together chefs, farmers and all of us ‘eaters.’ I love the energy and camaraderie in the room.” The event, which returns to the Upper Lodge at Ski Butternut, will feature a wide selection of tastings, all made with fresh ingredients from local farms. The evening also includes a silent auction with favorites like dinner at Blue Hill New York City, a cozy sheepskin from Mayflower Farm in South Egremont, and apple trees from Windy Hill Farm. In short, there are myriad reasons to attend: “The event celebrates local chefs, the farmers who grow the food, and raises money to help us Keep Farmers Farming!” Moulton added, in a nod to the nonprofit’s succinct mission.

“Shouldn’t the point be to celebrate the best of the best?” Irwin asked rhetorically. “Why take anything out of context?” he added, noting that regardless of what he makes, it will utilize in-season produce grown on the premises of his restaurant or gleaned from a cache of about five local farmers he tries to support as much as possible. In other words, there will be no asparagus spears in sight: The season is over. “The foundation of our restaurant is all about trying to support Berkshire grown — in practice, not in name — and in turn, we are big supporters of Berkshire Grown as we have similar values,” Irwin explained on Monday afternoon in New Marlborough. Case in point? Customers are raving right now about his Toasty Carrots, a “bite” that hinges on roasted Mill River carrots paired with burrata, Cantina kale pesto, hazelnuts and aged blueberry balsamic. And Irwin’s reply to those customers? “You should go by the farmers’ market and tell [Jan Johnson].” It’s what he calls diverting attention back to the source while delivering a salient message: You, too, should be buying really amazing carrots — not just any carrots from the grocery store. It’s a win-win mindset for both the farmer and the eater.

“Our work at Berkshire Grown is to keep farmers farming,” said Moulton. “The Harvest Supper has grown and evolved over the past 20 years, but at the heart of the event is the delicious food created by inspired chefs, and a vibrant community that supports farmers. I encourage people to come for the tasting dinner, bid on auction items, and visit with the folks who grow and produce our local food.”  The organization is thrilled to welcome chefs from Berkshire Mountain Bakery Cafe, Cantina 229, CMC:Berkshires, Cranwell Resort, the Gateways Inn & Restaurant, Gedney Farm, the Hotchkiss School, H.R. Zeppelin Fine Handmade Chocolates, John Andrews Farmhouse Restaurant, Kripalu Center for Yoga & Health, nAtURAlly’s Kitchen, the Old Inn on the Green, Prairie Whale, SoCo Creamery, 20 Railroad Public House and Williams College. Complimentary drinks will also be provided by Barrington Brewery, Berkshire Mountain Distillers, Big Elm Brewing, MS Walker Wines and Barrington Coffee Roasting Company. Moulton added that, “We are deeply grateful to our network of supporters — we couldn’t create this wonderful event without them.” Major supporters this year include Berkshire Natural Resources Council, Laurily Epstein, Benno Friedman & Stephanie Blumenthal, Roberta and Steven Haas, tsmit limited inc., and Windy Hill Farm.

Irwin will be serving up food and drink on Monday night — and even his restaurant’s high-end craft cocktails are infused with local flavor, quite literally, stretching from honey gleaned in nearby Mill River to fistfuls of fresh mint from the restaurant garden. Guests can look forward to tasting his dedication in each bite (or sip) of whatever he serves up, and the commitment to this way of life comes full circle: “I support Berkshire Grown in virtually everything that they do,” Irwin explained. “Not only do I think it’s a great cause, but it also plays in the community more than anything else by bringing people together, educating [them] and supporting farmers, which I believe in. If somebody else believes in that and makes it their mission, I’m totally behind them.”

NOTE: The dinner is by reservation only. Tickets are $75 for Berkshire Grown members and $100 for non-members. For those under the age of 40 and Farmer Members of Berkshire Grown, $40 tickets are available. Tickets sell out and are available via the Berkshire Edge calendar or by calling (413) 528-0041. All proceeds benefit Berkshire Grown, supporting its Buy Local campaign as well as its Share the Bounty project, which buys shares in local farms and distributes the fresh food to food pantries.