Combine chocolate squares and 1/2 cup butter in the top of a double boiler. Bring the water to a boil; reduce heat to low, and cook until the chocolate and butter melt, stirring occasionally. Set aside.
Combine eggs, sugar, and vanilla in a medium mixing bowl; beat at medium speed of an electric mixer until blended. Add flour and reserved chocolate mixture. Mix well.
Preheat waffle iron. Drop dough by 2 teaspoonfuls onto iron. Close iron, and bake for 1 to 1 1/2 minutes or until done. Let cool on wire racks. Continue cooking cookies until your dough is gone.
Top with frosting once they are cool.
Cream butter; add cocoa, beating well at medium speed of an electric mixture. Gradually add powdered sugar, milk, and vanilla, beating until smooth.