2.a. Food which
1) grows from the ground and
2) will spoil altogether if ground, chopped, crushed or grated before the Festival
may be so prepared on Yom Tov, in the manner adopted on a normal weekday, but only for use on that same day of Yom Tov. (See, however, paragraph 7 below, regarding the use of a kitchen mincer or grinder.)
2.b. Thus,
1) bananas may be mashed with the prongs of a fork,
2) apples may be scraped on a grater,
3) onions may be chopped very fine, with a large
chopping-knife specially designed for the purpose, in the manner which one is accustomed to use on a normal weekday,
4) cooked vegetables may be passed through a strainer to cream them, and
5) boiled potatoes may be mashed, to make them into a puree
2.c. For the laws concerning Yom Tov which occurs on Friday, see Chapter 2, paragraphs 10 to 16.