Buttermilk and Sansho Pepper Crispy Fried Chicken

In this recipe I use two ingredients that have a remarkable affinity with chicken – Japanese sansho pepper and buttermilk. Sansho pepper is a Japanese spice made from the ground peppercorns of the native prickly ash tree, a cousin of the Sichuanese pepper tree. Sansho pepper has a peppery-citrus flavour with a long residual heat. Buttermilk, though not a Japanese ingredient, makes for a fantastic chicken marinade – despite its name, buttermilk is neither buttery nor creamy, it is in fact ra