Joe Bastianich — partner of Mario Batali and co-owner of Babbo, Del Posto and Eataly — continues to lose friends and pique palates with his new memoir, “Restaurant Man.” Among those targeted in his searing tome is Le Cirque legend Sirio Maccioni, whom Bastianich brands as “facing oblivion,” with “customers who are all dead or dying.” He says of Maccioni, “I really don’t dislike the guy although he always treated me like a piece of [bleep].” Customers loyal to Maccioni’s high-end haunts, including Osteria del Circo, have come out swinging. “I wish I had a house account at some of your venues so I could cancel them after reading about your ungracious and unkind remark about Sirio Maccioni,” Whitney Radio president and CEO William O’Shaughnessy writes in a blistering letter to Bastianich obtained by Page Six. “I’m absolutely at a loss why you would attack one of the greatest statesmen of your own profession.” The angry missive is the latest to big-mouthed Bastianich. Esquire’s John Mariani called him “vile” and “duplicitous” this week for dubbing the food critic “a self-righteous, condescending p – – – k.” Maccioni, meanwhile, who’s taking over Le Caprice in the Pierre, celebrated his 80th birthday this month at Le Cirque. Guest Martha Stewart blogged, “Throughout the years, Sirio has always been the most charming gentleman and restaurateur who always hires the best chefs. I love eating at Le Cirque.” In a “Today” interview with Matt Lauer yesterday, Bastianich said of his book, “I am telling the stories of my life in a true way . . . the book is truthful and honest,” and “[stories of] food critics who trade free meals for reviews . . . those are the stories of my life.”