Preheat oven to 400 degrees Fahrenheit.

In a large bowl, cream butter (and shortening, if applicable) and sugar with a mixer for several minutes until light and fluffy.

Add eggs to the mixing bowl and combine well.

In a small bowl, add baking soda to molasses, stirring well, then stir in grated fresh ginger.

Add the molasses mixture to the butter and sugar mixture and mix until combined.

In a separate large bowl, sift together flour, dried ginger, cinnamon, allspice, and salt.

Alternately add the dry ingredients and buttermilk to the molasses mixture, beginning and ending with the buttermilk. Mix just until combined.

Stir in crystallized ginger chunks.

At this point, the dough can be covered and kept in the fridge for several days. If so, bring the dough to room temperature before baking.

When ready to bake, spoon the batter into well-greased muffin cups.

Optionally, sprinkle the tops with a little sugar.

Bake for 15 minutes, or until a toothpick inserted into the muffin comes out clean.