When it comes to operating a hamburger dynasty, there are no sacred cows.McDonald's, the fast-food chain that converts nearly 1.4 million cattle into ground beef sandwiches each year, proved that last week when it announced plans to open three all-vegetarian restaurants in India next year.In trying to capture its share of the global market, McDonald's is no stranger to innovation and experimentation. Take a trip to the Golden Arches in Norway and you can buy a McLak -- a salmon burger with dill sauce. In several countries in the Middle East and North Africa, you can buy a McArabia sandwich -- slices of grilled kofta, or savory meatloaf, nestled in a thick pita wrap, topped with lettuce, onions, tomatoes, garlic mayonnaise and cumin.Stop at a McDonald's in the Netherlands, and you can feast on a McKroket -- a pastry containing beef stew that is deep fried, topped with a creamy sauce, and placed between two buns. Closer to home, in the president's home state of Hawaii, breakfast at the Golden Arches can include Spam and Eggs, traditionally served with sides of steamed rice and Portuguese sausage.McDonald's already has 270 outlets in India, serving a combination of nonbeef meat and fish sandwiches, like the Maharaja-Mac (two chicken patties, cheese, lettuce, onion and tomato on a sesame seed bun) along with vegetarian fare, including the McSpicy Paneer (breaded, deep-fried cottage cheese chunk dotted with mustard and served on a sesame bun).I suspect that all-vegetarian McDonald's outlets could catch on in selected cities in the United States -- college towns outside the Biscuit Belt, for starters -- if an imaginative menu is offered, and if the restaurant chain abstains from sins of the past, like adding beef flavoring to its French fries.Here are a few suggestions:Eggplant McMuffin -- Breaded, deep-fried eggplant slice topped with slice of melted provolone cheese and dollop of marinara sauce, served on toasted English muffin.Big Mac-N-Cheese -- Three-layer sesame seed bun filled with baked macaroni and cheese topped with breadcrumbs, pickles, onions and special sauce.Filet-O-Knish -- Generous slice of deep-fried mashed potato dumpling topped with melted American cheese and tangy tartar sauce in a lightly steamed bun.Hippie Meal -- Start with a Tofunwich -- a spicy tofu burger topped with cool sprouts and warm melted brie -- and add a pack of organic pear slices, a granola bar and a container of soy milk, and you've got a complete boxed meal. Add a prize, like a Ty Beanie Baby carbon footprint or sad-eyed harp seal, and it's icing on the cinnamon rice cake dessert!