Preheat oven to 350°F. Grease and line a 9×9 baking pan with parchment paper.
In a standing mixer fitted with a paddle attachment, cream the butter, brown sugar, and molasses together until light and fluffy, about 2 minutes.
Add in the egg, spices, fresh ginger, and salt, whipping an additional minute. Fold in flour, mixing only until combined.
Transfer dough to prepared baking pan, patting down evenly. Bake for 15-18 minutes, until a knife inserted in the center of the shortbread comes out clean. Allow to cool while you make your caramel.
In a small saucepan over medium low heat, combine the sweetened condensed milk, sugar, butter, and honey. Use a rubber spatula to mix slowly but continuously for about ten minutes. The mixture will slowly turn a light golden color and begin to pull away from the sides of the pan. Heat until mixture reaches a nice golden caramel color, then immediately remove from heat and mix in salt.
Pour mixture over ginger shortbread, and use spatula to spread evenly. Place in the fridge to harden completely, about 2 hours.
Once the bars have cooled, make your chocolate layer. Prepare a double boiler over medium heat. Chop the chocolate and pour 3/4 of it into a glass or metal bowl. Melt over double boiler until completely melted. Remove from heat, fold in remaining 1/4 of chocolate, and allow to sit for 5 minutes.
After 5 minutes, stir the mixture, making sure all the chocolate has melted completely. Pour over chilled bars, then place back in fridge to harden.
Cut into 1″x2″ bars and serve! Will last up to 1 week when sealed tightly in a container in the fridge.