Udon noodles are wide Japanese noodles made from wheat flour.  If you can't find udon noodles in your supermarket or Asian grocery store, you can substitute any dried, flat wheat noodle.

*  'Al dente' literally means 'to the tooth'.  When cooked 'al dente', the pasta should be slightly firm to bite, but cooked through.
*  Pappardelle is a wide ribbon pasta.  If you can't find or don't want to use pappardelle, you can substitute fettucini or spaghetti.