1. Heat oven to 350°F. Stir together flour, cocoa, baking soda and salt; set aside.
2. Beat butter and sugar in large bowl with mixer until fluffy. Add eggs and vanilla; beat well. Gradually add flour mixture, beating well. Stir in peanut butter chips. Drop by rounded teaspoons onto ungreased cookie sheet.
3. Bake 8 to 9 minutes. (Do not overbake; cookies will be soft. They will puff while baking and flatten while cooling.) Cool slightly; remove from cookie sheet to wire rack. Cool completely. Makes about 54 cookies.
PAN RECIPE: Spread batter in greased 15-1/2x10-1/2x1-inch jelly-roll pan. Bake at 350°F 20 minutes or until set. Cool completely in pan on wire rack; cut into bars. About 4 dozen bars.
ICE CREAM SANDWICHES: Prepare CHEWY CHOCOLATE COOKIES as directed; cool. Press small scoop of vanilla ice cream between flat sides of cookies. Wrap and freeze.
HIGH ALTITUDE DIRECTIONS:
-- Increase flour to 2 cups plus 2 tablespoons.
-- Decrease baking soda to 3/4 teaspoon.
-- Decrease sugar to 1-2/3 cups.
-- Add 2 teaspoons water with flour mixture.
-- Bake at 350°F, 7 to 8 minutes. Yield increases to about 6 dozen.