1In a large bowl, knead almond paste to soften. Mix in egg whites. Knead in confectioners' sugar 1 cup at a time. Add vanilla. Knead until marzipan feels like heavy pie dough.
2Wrap tightly in plastic, and store in refrigerator in a sealed container. To use after storage, let stand at room temperature until soft, then knead briefly.
Footnotes
Notes
A few drops of food coloring may be kneaded into portions of marzipan until the desired shade is achieved.
If marzipan stiffens up, just knead in a little water, egg white or corn syrup.