Why do I get the numbing sensation after eating Sichuan Mapo tofu or any other Sichuan spicy dishes?

The numbing sensation in Sichuan Mapo tofu comes from the use of Sichuan peppercorns, which are a key ingredient in many Sichuan dishes. Sichuan peppercorns contain a compound called hydroxy-alpha-sanshool, which stimulates the touch receptors in the mouth and creates a tingling, numbing sensation. This sensation is sometimes referred to as "ma" in Sichuan cuisine, which means "numbing."

In addition to Sichuan peppercorns, Mapo tofu also typically includes spicy ingredients such as chili bean paste or chili oil, which can further enhance the heat and numbing sensation in the dish. Together, the combination of Sichuan peppercorns and spicy ingredients give Mapo tofu its characteristic flavor and sensation.