Along with his now former business and romantic partner, Reinhardt Lynch, he began a catering business in 1972 in Virginia's Blue Ridge Mountains. In 1978, O'Connell and Lynch opened the Inn at Little Washington in an abandoned gas station. Opening first for friends and acquaintances on January 28, 1978, then officially to the public on February 1, 1978, the Inn at Little Washington was met with immediate success and notoriety despite antagonism from many locals. Three weeks after opening, a food critic for The Washington Star, John Rosson, visited the Inn for dinner after the insistence of one of his loyal readers. Familiar with Rappahannock County, Rosson accepted the challenge to visit the new restaurant in the sleepy town of Washington, VA, located 67 miles west of the younger but more recognizable Washington D.C. Upon visiting for the first time, he was amazed by what he experienced. To be certain that it was more than just a "fluke" or a "series of fortunate events," Rosson would return the next week. Upon doing so, equally astonished by the depth and breadth of his experience, he thought it best to introduce himself, despite regarding his anonymity as a food writer as a well-guarded secret. The critic had met his match at least in terms of his ability of uncovering any weak underside of a fledgling new entity, especially one centered in the midst of a sparsely populated village of less than 300 residents. By introducing himself to the new chef and proprietor, he gave a not-so-subtle warning that was more prophetic than conciliatory: "I am going to write a story about you that is going to change your life. You are going to need to hire someone full time just to answer your phone!"In April, 1978, John Rosson's article was printed, proclaiming Patrick O'Connell's Inn at Little Washington as "the best restaurant within 150 miles of Washington D.C." The Inn has won the Mobil Travel Guide’s Five-Star Awards for its restaurant and accommodations for 14 years. In 2018, the Inn received a coveted three-star rating from the Michelin Guide. The International Herald Tribune rated it as one of the Top Ten Best Restaurants in the World. The Zagat Survey for Washington, D.C. rated it number one in all categories for 14 consecutive years.
Awards and recognition
O'Connell was one of the first American chefs courted by the France-based Relais & Chateaux. He is recognized as one of their "Grands Chefs". He has been called "The Pope of American Cuisine," and anyone who has been invited to dine in the kitchen is welcomed with the pageantry of a religious ceremony. He has won numerous awards including Outstanding Chef in America in 2001 and Best Chef in the Mid-Atlantic region in 1993, both awarded by the James Beard Foundation. In 2019, he was awarded their Lifetime Achievement Award. He is a member of the American Culinary Federation and was inducted into the ACF Hall of Fame in 2009. In 2019, O'Connell was awarded the National Humanities Medal.