Wash the spinach thoroughly and roughly chop it. Bring lightly salted water to the boil in a saucepan and add the spinach to the water. After 2 minutes, quickly scoop the spinach out of the water and rinse in a colander with cold water. (You can of course also drain the spinach, but I think the cooking water is too good to throw away.) The spinach is then set aside to drain.