Preheat the oven to 300 F.In a medium saucepan, heat the cream over medium heat.Add ginger and cook until a film forms on the surface.Remove from heat.Cover and let steep for 30 min. Remove the ginger from the cream using a slotted spoon. Return the cream to the stove, over low heat, add ¾ cup of the sugar and stir until the sugar dissolves. Remove from the heat and allow to cool slightly while preparing the egg yolks.
Place the egg yolks in a bowl.Whisk until well blended (they should appear pale yellow and slightly frothy).Gradually add 1 cup hot cream to the yolk mixture, whisking constantly to mix.Then pour the warm egg yolk mixture into the remaining cream and whisk together to blend completely. Add The Big O ginger liqueur and mix well. Strain through a fine mesh sieve into a pitcher.
Arrange 8 flameproof, ¾ cup custard dishes in a large baking pan.Evenly distribute the egg mixture among the cups.Pour the boiling water into the baking pan to reach halfway up the sides of the custard dishes.Transfer the baking pan of custards carefully to the preheated oven and bake until the custards are set, about 1 hour.Remove the custards from the pan. Cool, cover, and refrigerate for about 2 hours.
Preheat the broiler.Sprinkle remaining sugar, about 1½ teaspoons over the top of each custard.Place the dishes in the broiler and broil, watching very carefully, until the sugar melts and turns golden, about 1-2 min. Serve immediately.