1. In a large heavy-bottomed pan mix the half and half with the sugar, espresso powder, cocoa powder, and vanilla. Heat the mixture over medium heat until it begins to steam (but before it begins to simmer) about 180°. Reduce the heat as necessary to hold the cream at this temperature for 20 minutes, stirring often. Do not boil.
2. After 20 minutes of steeping, remove the cream from the heat. Strain the mixture through a fine-mesh strainer.
3. Stir in the maple syrup, nutmeg and pinch of kosher salt (affiliate link) into the strained half and half mixture. Then stir in the Irish whiskey.
4. Stir the Irish Cream occasionally as it cools, uncovered, on the counter. Once cool, transfer it to a sealed bottle or container. Store in the refrigerator until ready to use. Shake well before serving.
5. Homemade Irish Cream Liqueur should be used within 2 months (kept in the fridge at all times). If you won’t use it within that time, I’d recommend freezing it to make some tasty Irish Cream ice cream. 

*rinse the used vanilla pod under cold water and let it air dry, then add to your bottle of vanilla, it’s the gift that keeps on giving!