Heat up a pot of water(i use a brining pot) to a simmer, pour it down any drain and that clog is gone.

You don’t need to boil anything and the exact temperature does not matter.

fill a big pot with tap water, heat it up to a near simmer, dump it directly down the drain.

That’ll give the clog a good punch and the weight of the next gallon or two you heated up will get rid of the rest of it.