Szechuan cuisine (四川菜 or 川菜) is a style of Chinese cuisine originating in Sichuan Province of southwestern in China which has an international reputation for being hot and numbing (麻辣), because of the common ingredient Sichuan peppercorn(花椒).  Although the region Sichuan is now tomanozed as Sichuan, the cuisine is still sometimes spelled Szechuan in the West.   Broad bean chili paste (豆瓣醬 or dòubànjiàng) is also a staple seasoning in Szechuan cuisine.

Some well-known Szechuan dishes include Kung Pao Chicken and Twiced Cooked Pork, Ma Po Tofu.

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Hunan cuisine, sometimes called Xiang cuisine (湖南菜 or 湘菜; hú'náncài or xiāngcài), consists of the cuisines of the Xiang River region,Dongting Lake and western Hunan Province, in China.

Hunan cuisine is one of the eight regional cuisines of China and is well known for its hot spicy flavor, fresh aroma and deep color. Common cooking techniques include stewing, frying, pot-roasting, braising, and smoking. Due to the high agricultural output of the region, ingredients for Hunan dishes are many and varied. Hunan is known for its liberal use of chilli peppers, shalots and garlic. 

Some well-known Hunan dishes includes Orange Beef, Hunan Chicken, Sizzling Rice soup. 

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Beijing cuisine (京菜 or 北京菜; jīngcài; literally "capital cuisine") is a cooking style in Beijing , China. It is also formally known as Mandarin cuisine.

Since Beijing has been the Chinese capital city for centuries, its cuisine has been influenced by culinary traditions from all over China, but the cuisine that has exerted the greatest influence on Beijing cuisine is the cuisine of the eastern coastal province of Shangdong.  "The Emperor's Kitchen" (御膳房; pinyin: yùshànfáng) was a term referring to the cooking places inside of the Forbidden City, Beijing where thousands of cooks from the different parts of China showed their best cooking skills to please royal families and officials. Therefore, it is at times rather difficult to determine the actual origin of a dish as the term "Mandarin" is generalized and refers not only to Beijing, but other provinces as well. However, some generalization of Bejing cuisine can be characterized as follows: Foods that originated in Beijing are often snacks rather than full courses, and they are typically sold by little shops or street vendors. There is emphasis on dark soy paste, sesame paste, sesame oil, and scallions, and fermented tofu is often served as a condiment. In terms of cooking method, methods relating to the different way of frying is often used.

Some well-known Beijing dishes include Pekign Duck, Hot & Sour Soup, Moo Shu dishes, Pork Dumplings.

                                                                                                        -----From Wikipedia