In a mixing bowl, beat the butter or margarine and sugars together until fluffy. Add the vanilla and egg and beat an additional minute.
In a separate bowl, stir together the flour, cocoa, baking soda and salt. Slowly add to the mixing bowl and stir just until combined. Stir in chocolate chips by hand.
Roll heaping tablespoons of dough into a ball and place on baking sheets. Bake at 375 degrees for 9-11 minutes. Cool on a wire rack. (Makes about 3 dozen cookies.)
Notes
After our cookies were completely cooled, I frosted them with this buttercream frosting recipe that I tinted pink. Then my little girls helped decorate them by adding a gummy heart to the top of each cookie. Hopefully they’ll be a hit at school tomorrow.