I can remember as a kid getting totally smashed at Xmas on hard sauce and plum pudding. My mother would hang puddings in cheese cloth from just after Thanksgiving and pour brandy on them every day for a month. She served them flaming adorned with a sprig of holly. The pudding was cut and served while still flaming. The hard sauce was spooned onto the warm pudding after the flames died out.
Hard sauce is basically butter, confectioner's sugar and booze, usually rum or brandy (or rum or vanilla extract). Bourbon might work also. In fact, a bourbon hard sauce sounds delicious (GWiv, are you paying attention?). If you use liquor instead of a flavoring, you should let some of the alcohol evaporate before adding it. Anyhow, when you make the hard sauce, it should have the consistency of soft-spread margarine or whipped butter. It must be served from the refrigerator in a chilled metal bowl. That is what makes it "hard". The cold sauce has the consistency of cold margarine. It needs to be served on something warm so it melts. A small ice cream scoop works well to serve it with. It starts as a pretty solid round ball that melts and soaks into the warmed desert. It would not work on pumpkin pie, but it would be great with warm gingerbread. You could flambe the gingerbread like a figgy pudding with a high alcohol brandy or congac (100+ proof or > 50% ABV) then scoop the hard sauce onto the warm bread. Again, a high alcohol bourbon might work well also. It makes for a great show when the lights are dimmed and the flaming desert is cut and served while still burning, or if you are not into pyro-technics and boozy deserts, you could just warm it in the oven.