Step 1 In a medium saucepan, heat the coconut cream and sugar over medium heat just long enough to dissolve the sugar and blend with the cream, stirring frequently. Remove from heat and pour the mixture into a medium bowl to cool to room temperature.
Step 2 In a large bowl, whisk the eggs until blended. Whisk in the essence if using, then whisk in the cooled coconut cream mixture until thoroughly incorporated.
Step 3Strain the mixture through a dampened muslin cloth or fine wire mesh strainer into an oiled 8-inch square baking dish.
Step 4Place the dish in an Asian steamer set over simmering water and cover. Alternatively, place the custard on a rack set over simmering water in a large roasting pan and cover. Steam over medium-high heat until the custard is set (a knife inserted near the center should come out clean), about 20 minutes. Remove from heat.
Step 5Serve custard in serving bowls or cut into slices, 3 inches by about one-half inch thick, on top of sticky rice with coconut milk (see accompanying recipe).