Preheat oven to 375 degrees F (190 degrees C). Grease cookie sheets.
In a large bowl, cream together the butter and sugar until light and fluffy. Add the vanilla and egg; beat until well blended.
In a separate bowl, sift together the flour, cocoa, baking powder and salt. Gradually add to the creamed mixture, stirring until well blended.
Stir in the chocolate chips and walnuts. Drop the dough by teaspoonfuls onto the prepared cookie sheets.
Bake for 8 to 10 minutes in the preheated oven. Allow cookies to cool on baking sheet for 5 minutes before transferring to a wire rack to cool completely.
Interesting Facts
These cookies are a great way to use up any leftover semi-sweet chocolate chips you may have.
Chocolate Drop Cookies II will stay fresh in an airtight container at room temperature for up to a week.
Adding nuts to your cookies adds a nice crunch and flavor, but you can also leave them out if you prefer.