Heat oven to 375ºF. Line a baking sheet with parchment paper and set aside.
Into a medium bowl, sift together the flour, baking soda and salt.
With a mixer, beat the butter, sugar and brown sugar together on medium speed for 3 to 5 minutes, until the mixture is smooth, creamy and light in color.
One at a time, beat in the eggs, then add the vanilla and Irish cream.
Gradually stir in the flour mixture until thoroughly combined.
Stir in the chocolate chips and cacao nibs.
Onto the prepared baking sheet, drop tablespoons of the dough 2-3 inches apart. Sprinkle each one with a pinch of demerara sugar.
Bake for 9-11 minutes or until golden brown. Remove from oven and let cool for 1-2 minutes on the baking sheet, then transfer to a wire baking rack to cool, or serve warm.
Store in an airtight container at room temperature for up to 5 days. For longer storage, wrap in plastic wrap and freeze.
Notes
Quality ingredients make a big impact in baking. Always use a quality vanilla extract if possible. If you can afford it, Irish butter like Kerrygold is wonderful to bake with. Feel free to substitute other creamy liqueurs like Rumchata or Amarula. You can also use milk chocolate chips for a sweeter cookie or dark chocolate chips if you like things more bittersweet.Cacao nibs are totally optional, but they do add an extra chocolatey crunch.