Which province is the birthplace of donkey meat fire?

Burning donkey meat is a very popular traditional snack in northern China. Originated in Baoding and Hejian, Hebei Province, and widely spread in the Central Plains of Hebei Province. Donkey meat marinated in soup stock is added to crispy fire. But the donkey fire in Baoding is round, and the donkey fire in Hejian is rectangular. According to historical records, the burning of donkey meat originated in the second year of Ming dynasty, namely 1400.