In big cities like Shanghai and Beijing, you will see authentic American restaurants, which are owned and operated by Americans and serve their hometown. For example, I went to a Texas restaurant in Beijing several times. The owner is from Texas. They serve peppers, tacos, hamburgers, steaks, onion rings and other Texas foods, just like you can eat in Texas.
However, even in big cities, other restaurants may be very unpopular. Usually they don't flaunt themselves as Americans, but write western food on the signboard. Now that you have this title, you may think that you can get some French or Spanish dishes, but if you look at the menu, you will find that this is just American cooking, usually a variant of American cooking.
You usually find some salads, sandwiches, steaks, hamburgers, pizzas, pasta and shrimps. Among them, salad may be the safest choice. Others may let you down.
The steak is likely to be overcooked, crisp and covered with black pepper sauce. Pizza will get wet. There will be too much cheese and ingredients, and every little tomato. If there are tomatoes, it is probably ketchup. Canned fruit is often put on pizza. Spaghetti is spaghetti with ketchup on it. The meat in the sauce is the same as the meat on the pizza.
But once in a while, you will find a good restaurant. Only sometimes, you will find that a restaurant can really cook medium-rare steak, make spaghetti with real tomatoes, and know how to bake real pizza with the right ingredients.
Of course, for safety, you can also go to big brand fast food chains. KFC is everywhere. You can find McDonald's, Starbucks, Burger King and Pizza Hut in most cities.
Here are some pictures of hamburgers and other western food I met in China.
There are hamburgers, onion rings and pizza in the back.
Fish and chips with mayonnaise and tomato sauce. Hamburgers and French fries. There is an egg, lunch meat, bacon and salad in the hamburger. Chicken burger, similar to KFC's, but much bigger. Pork burger with French fries, salad, tomato sauce and honey mustard sauce. Grilled spaghetti with meatballs. Hamburger bread is sprinkled with sausage, bacon, lunch meat and salad, and topped with honey mustard sauce.