Combine in a mixing bowl:

1/2 cup (1 stick) butter
1 cup brown sugar
1 cup molasses

Combine in a 1 cup liquid measure:

1 cup boiling water
2 tsp. baking soda

Place the baking soda in the bottom of a 1 cup liquid measuring cup. Fill with boiling water, allowing the water to run off into bowl while filling (not too much; just the overflow) and refill the cup to a full 1 cup measure.

Mix together:

3 cups all-purpose flour
1 tsp. of each ginger, cinnamon, cloves, allspice and nutmeg

Add to the above ingredients in mixing bowl.

Beat well:

2 eggs

Add beaten eggs to bowl, stirring to combine.

Bake at 350°F for 30 minutes in a 9x13-inch greased pan.