Boil sweet potatoes until tender and drain. Add molasses, honey, vanilla, brown sugar, nutmeg, and cinnamon. Mash by hand then beat until smooth with an electric beater.
Preheat oven to 325 degrees F. Pour the cream into a saucepan and add the vanilla bean seeds, and the pods. Over medium low heat slowly bring to a boil, then remove from heat, cover pan and set aside for at least 15 minutes to allow the flavors to infuse. In a large bowl, whisk together the egg yolks and gradually add 1/2 cup of the sugar whipping until you see a change in color. After 15 minutes remove the vanilla pods from the cream mixture. Then slowly incorporate the cream mixture into the egg yolk mixture a little at a time, whisking constantly as you go.
Lightly grease 6 to 8 (4 or 6-ounce) ramekins. Add even amounts of the sweet potato mixture to the ramekins. Then fill the ramekins each 3/4 full with the custard mixture.
Place the filled ramekins in a roasting pan and prepare a bain marie by adding hot water to the pan so that the water level is halfway up the side of the ramekins. Be careful to avoid splashing any water into the ramekins. Bake in the oven for 40 to 45 minutes, allow to cool and then refrigerate for at least 2 hours before serving. (You can do this way in advance if you wish.) Just before serving remove from the refrigerator and allow to warm up a little. Then divide the remaining 1/2 cup of sugar among the ramekins sprinkling some on the surface of each cup. Using a blow torch, melt the sugar to form a crispy sugar "crust" on the top of each. This custard could be served with fruits of the season.