Chewy chocolate cookies

Chewy chocolate cookies by Heather
1 cup butter, softened
2 cups sugar
2 eggs
2 teaspoons vanilla
2 cups flour
3/4 cup cocoa
1 teaspoon baking soda
1/2 teaspoon salt
2 cups peanut butter, chocolate or white chocolate chips (optional)

Cream butter and sugar; add eggs and vanilla and mix well. Combine dry ingredients and blend in. Add chips as desired (not necessary but fun to add). Drop onto ungreased cookie sheet. Bake 6-9 minutes at 250 degrees. Do not over bake. Makes approx 4 dozen