HaMotzi: Forgot To Wash

Situation You said ha'motzi without having washed your hands first.
What To Do Up until the time you say birkat ha'mazon, you must interrupt your meal and wash your hands. 
Note Say al netilat yadayim ONLY if you will still eat at least 1.9 fl. oz. (56 ml) of bread afterward; if you will eat less than 1.9 fl. oz., wash without a blessing.