Wash one-half peck of spinach, discarding the coarser stems; place in a saucepan; sprinkle over it a half teaspoonful of salt; over this pour one cup of boiling water; cover closely and let boil over a moderate fire for two minutes. Now to insure a good color, finish cooking without a cover, giving the spinach an occasional stir. The time required for cooking will depend very much upon the age of the spinach. When tender turn into a colander, drain and press well to remove all water, then cut fine, return to saucepan; add butter, pepper (salt if needed) and a teaspoonful of vinegar. Reheat and place in serving dish. Sprinkle over the top the chopped whites of two hard boiled eggs, then the yolks pressed through a vegetable press. Put into a hot oven for about two minutes before serving.