Wölffer Estate Vineyard’s Summer in a Bottle rosé is practically a local currency in the Hamptons—spotted everywhere from Duryea’s lobster Cobb to Surf Lodge’s now-iconic chicken tender tower. But for those who prefer to sip straight from the source, there’s the vineyard’s beloved tasting room and ever-buzzing wine stand in Sagaponack.

A more serene setting lies just beyond: the Wölffer Estate Stables, a private haven owned by the family and rarely open to outsiders. That changed Thursday evening, when the stables played host to a rarefied dinner party co-hosted by the Italian purveyor of quiet luxury, Brunello Cucinelli.

Despite whispers of a summer storm, guests arrived undeterred—and dressed to the Cucinelli nines. Think cashmere cardigans, featherlight linens, and creamy silks in a tonal palette of chalk, stone, and weathered earth. Ponies looked on from their stalls as guests mingled around a fountain-turned-Italian piazza, complete with carts piled high with tomatoes and aperitivo snacks.

“This was a single little farmhouse on potato fields,” Joey Wölffer told Vogue, reflecting on her family’s roots in the area. “I remember going through the fields and picking up bugs—which is weird, because I don’t like bugs—but it was just nothing for miles. You could see the beach from here. It’s obviously developed, but I think what’s great about this place is that it’s still got its roots.”

Indeed, while the dinner was staged with cinematic flair, the original barn from 1978 stood just steps away—a reminder of the family’s early beginnings. Guests, including Christie Brinkley and Sailor Brinkley-Cook, Alexandra Daddario, Lady Kitty Spencer, Tamron Hall, and Nicky Hilton Rothschild, explored the grounds with visible awe.

“It’s an odd coincidence that 1978 is the same year Brunello Cucinelli was founded,” noted Riccardo Stefanelli, CEO of the house. “The Cucinelli family is to Solomeo what the Wölffers are to East Hampton. Every time I come here, there’s this sense of care and beauty—of people taking responsibility for their place in the world. That’s something we share deeply.”

As golden hour faded into dusk, guests were served a no-frills-but-perfect plate of rigatoni in tomato sauce—perhaps a surprise, given the elegant surroundings, but a hit among those in attendance, including culinary talents Katie Lee Biegel and Sarah Wetenhall of The Hedges Inn.

And while Mr. Cucinelli himself once told me he limits himself to six noodles a day to maintain the perfect tailoring line, Thursday’s guests enjoyed a more generous helping—paired, naturally, with a glass of Wölffer’s Cabernet Franc.