Set Power Select at HIGH.
Prepare cooking bag according to package directions; place brisket, water and soup mix in bag.
Set in oblong baking dish; close bag with nylon tie or string; make 6 (1/2 in.) slits in top of bag.
Heat 5 minutes.
Set Power Select at LOW.
Heat 90 minutes or until beef is tender.
Let STAND 10 minutes before serving.