This is also a standard recipe (from the back of the peanut butter chips bag), but it is very good (and makes cookies that are chocolate dough with peanut butter chips in them).
Cream butter or margarine and sugar until light and fluffy in large mixer bowl. Add eggs and vanilla; beat well. Combine flour, cocoa, baking soda and salt; blend into creamed mixture. Stir in peanut butter chips. Drop by teaspoonfuls onto ungreased cookie sheet. Bake at 350 degrees for 8 to 9 minutes. (Do not overbake. Cookies will be soft. They will puff during baking, flatten upon cooling.) Cool on cookie sheet until set, about 1 minute; remove to wire rack to cool completely.
Makes about 6 dozen.