This may well be the definitive gingerbread.  We certainly tested enough alternative versions before we agreed upon it. ~ from The New Laurel's Kitchen

1/3 cup soft or melted butter
1 cup dark molasses or 2/3 cups blackstrap and 1/3 cup honey
1 egg
1 cup buttermilk or orange juice
2 1/2 cups whole wheat flour
1 tsp soda
1 tsp cinnamon
2 tsp powdered ginger
1/2 tsp salt
1/2 cup raisins
1 T orange zest (optional)
1/2 tsp mustard powder

Preheat over to 350 degrees.

Mix butter and molasses.  Beat in egg and add buttermilk or orange juice.  Sift together the dry ingredients and combine everything together.  Turn into a greased 9" x 9" square pan.  Bake 40 minutes