The substance is the same, but the texture is very different. If
farfel is all you have and
you're forced to use it in a recipe in place of matzo meal, you
should do the best you can
to pulverize it into the finest powder you can. Put 1/2 to 3/4
cup of farfel into a zip-top
plastic bag, lay the bag flat on the counter, and roll back and
forth over it with a rolling
pin or a glass jar.