Use a pot to boil water, rinse with sputum, and wait until the water is open. Wait for the water to boil again for a few minutes, let the blood of the cockroaches float out.
Turn off the fire and put the clams in the saucepan. Do not pour the original soup, filter it with a net spoon. I put the net spoon on the saucepan and pour the original soup directly from the net spoon into the saucepan. This preserves the taste of the cockroach and the soup is clearer.
Start a small fire and start cooking.
The yam is peeled and cut into pieces, washed and spared. Wait until the soup in the saucepan is hot and put the two into it.
A large chunk of ginger, scrape the skin, use a knife to take a few shots, split it, and put it in a saucepan.
At least 2 hours, preferably 3-4 hours, will be more and more fragrant.
Finally, add some chicken powder and salt to taste.