deb, for frozen shrimp, 1 TBS of salt and 4 cups of water boiled per 1 lb. jumbo for 4-5 minutes...
Throw shrimp into an ice bath (I use a colander) to stop cooking.
These are my most recent notes and the shrimp was perfect. It took 5 minutes for me but I say 4-5 mins. max so as not to overcook them. Even better would be to make a court bouillon for boiling, but I haven't tried that yet.