In a medium saucepan, combine the eggs, egg yolks, and maple syrup. Slowly whisk in the almond milk, making sure it mixes. Add in the cinnamon, nutmeg and vanilla.
Heat over low heat, whisking continually, until mixture thickens, but don't let the mixture get over 160° as that can cause separation.
Once thick, pour into a container and let cool at room temperature. Then refrigerate. It will thicken in the fridge as well, but still won't be as thick as traditional egg nog.
Store in fridge up to 4 days. Stir or shake before serving.
Notes
If the egg nog separates, use an immersion blender or regular blender to combine.