Bok Choi With Peanut Sauce

1 bag bok choi or 3/4 lb Napa cabbage

3 Tablespoons peanut butter

1/3 cup warm water

1-2 Tablespoons peanut or canola oil

Roughly chop bok choi.  Thoroughly mix peanut butter and water in cup (peanut butter dissolves better if water is warm).  Heat oil in wok or frying pan.  Add bok choi and cook several minutes until wilted, stirring frequently.  Add soy sauce mixture and cook for several minutes, until sauce has thickened