Sarah O'Kelley, who six years ago founded The Glass Onion with Chris Stewart, is leaving the popular West Ashley restaurant to concentrate on preparing for the Court of Master Sommeliers' advanced level exam.

"She's passed the first two exams, and when you get into the third, it's like studying for the bar," says Stewart, who will remain on as owner and executive chef.

O'Kelley has not yet been aaccepted to sit for the exam, but will learn in Septemeber whether her application is approved. In the interim, she says, she's reading a wine book every day; plotting a trip to TexSom, a major summer gathering of wine professionals in Dallas, and arranging to work the grape harvest in Beaune, France.

"It's slightly terrifying, but definitely worthwhile," she says of the formalized path to wine expertise.

Stewart predicts O'Kelley will open another Charleston business in the next year or two. "It'll probably be more wine-focused," he says.

"I think that's Chris looking into his crystal ball," O'Kelley says with a laugh. While she acknowledges an entreprenuerial streak, she isn't ruling out working for someone else. At this juncture, she says, it's premature to look beyond a year of intensive wine study.

"I put my heart and soul into The Glass Onion," she says. "It's like a breakup: I can't start dating right now."

O'Kelley confirms she'll stay in the area. She's very happy with her Folly Beach house, and hopes to spend the next two weeks tending to domestic projects which piled up while she worked restaurant hours.

"Like anyone in a crazy profession, I have a lot to catch up on," she says. "And I want to catch up with friends and family."

Stewart says The Glass Onion's customers shouldn't see any evidence of the transition. His wife, who makes and sells wedding cakes under the Flying Tricycle banner, will oversee the dessert program; O'Kelley served as the restaurant's head baker. "The style of everything is going to stay the same," Stewart says.

"This is good timing for us," he continues, alluding to the summertime event lull. "We've got a terrific staff, and we're excited."

O'Kelley says she'll miss the staff and loyal customers.

"Truthfully, it's bittersweet," she says.