This is gingerbread how gingerbread should be. You don't have to rifle through your cabinet for a million spices and you don't have to run to the store to buy Guinness or stout. The incredible richness and complexity is thanks to blackstrap molasses, which is powerful enough to mellow out the shrillness of ginger and to impart an earthy, caramelly flavor to the cake.
And please, make the frosting. Everything about it is spectacular, and the process of making it is a magical experiment (the baker's version of a baking soda and vinegar volcano). Yes, it's a little bit of work, but the cake itself comes together so easily that you'll have enough time to get out the stand mixer.
This recipe is very slightly adapted from Faith Durand at The Kitchn via The Splendid Table. —Sarah Jampel