Bri inng a large stock pot of water with half the salt to a boil.
Add the spinach and cook until just wilted (about 1 minute).
Drain the spinach in a sieve of colander.
Rinse with cold water until cold enough to handle.
Squeeze the water out of the spinach one fistful at a time.
Chop the spinach bundles into a 3/4 inch width.
(alternatively, use frozen chopped spinach, defrost it and drain it)