Combine brown sugar, molasses and spices in a saucepan. Heat to boiling over medium heat stirring constantly. Boil 1 minute, take off heat.

Place butter in a large mixing bowl. Pour sugar mixture over butter and stir until butter melts. Blend in eggs.

Stir 2 cups flour and baking soda together. Gradually mix into the butter/sugar mixture. Mix in additional flour to make dough stiff. Shape dough into a ball, wrap in plastic wrap and refrigerate a few hours or overnight.

Cut dough into quarters. Shape one quarter at a time into balls keeping the other dough in the fridge. Use rounded teaspoonful of dough for each ball. Place on ungreased cookie sheet. Bake in preheated 350 degree oven for 10-12 minutes until golden. Cool on wire racks.