In a blender, blend the egg yolks and maple syrup until light and fluffy. Alternatively, use a hand held mixer.
Heat over medium-high heat, the coconut milk, nutmeg and cinnamon until simmering, but not boiling.
Once heated, turn the blender on low and very slowly stream in the hot coconut milk in the hole in the top of the blender (while the blender is running), into the egg mixture. Alternatively, slowly stream in the heated coconut milk while mixing with a hand held mixture.
Transfer the mixture back to the saucepan over a fine-mesh strainer to catch any lumps that may have potentially formed, and heat over medium heat until the mixture is thick and coats a wooden spoon, stirring/whisking constantly.
Turn off the heat and add in the vanilla and bourbon if using.
Chill completely. And then serve with an additional grating of nutmeg if desired.
In place of maple syrup, feel free to use coconut sugar or granulated sugar and increase up to ⅓ cup if you like a really sweet beverage.
Dairy-free eggnog will store in the refrigerator for up to 4 days. You may need to blend to incorporate coconut milk solids before serving, as coconut milk can solidify quickly in the refrigerator.
If you are not dairy-free and don't want to try out using coconut milk, this recipe works perfectly using whole milk as well.
Feel free to increase the sweetener up to ⅓ cup if you like really sweet beverages.