Heat an earthen pan slowly and melt in it a tablespoonful of butter; add a teaspoonful of salt, a smaller quantity of pepper and a small onion minced very fine; or in place of the onion, use parsley, and sweet herbs, or a combination of all together as you prefer.

Drop in the eggs one at a time; do not stir, but let them brown a little; turn carefully and brown on the other side.

In Spain and Mexico they are served in the dish in which they are cooked, and as hot as possible.