Place 4 cookie sheets into the freezer for 15 minutes, or until well chilled. Preheat oven to 400°.

Combine sugars and margarine in a mixer bowl until well blended. Add eggs and vanilla extract, beating until fluffy.

In a separate bowl, sift together flour, cocoa, and baking soda; add to margarine mixture at low speed. Stir in chocolate chips until well combined. Batter will be very stiff.

Gather four or five marshmallows in the palm of your hand. Using a tablespoonful of dough, wrap the marshmallows together, completely encasing them in the dough, and form a 2-inch ball. Repeat until all dough and marshmallows are finished.

Place balls on ungreased cookie sheets, 2 inches apart. Bake for 10 to 12 minutes and immediately transfer to cool, flat surface.