The formula of Leshan fried skewer bittern oil is: rapeseed oil 12kg, onion 800g, ginger 500g, onion 300g, star anise 50g, fragrant fruit 8g, fennel 20g, kaempferia kaempferia 12g, fragrant leaves 12g, clove 3g, tsaoko 9g, cinnamon 25g, dried tangerine peel 4g, etc.
Preparation method of bittern oil: mashing onion, ginger and celery, cutting onion into sections, and soaking spices in clear water for half an hour; Pour rapeseed oil into a hot pot. When it is 90% hot, add chopped green onion, ginger, celery and onion respectively. When fried to golden brown, remove the dregs from the pot and discard them. Boil the spice soaked in clear water in boiling water for five minutes, take it out and drain it, then pour it into an oil pan, simmer slowly, then turn off the fire, soak the spice in the oil for one day, and take out the spice residue after one day to get the bittern oil.