Melt wagyu fat in a pan. Add whisky to a container and pour the fat over. Seal and gently shake to mix over the course of 30 minutes. Chill in the freezer overnight. Strain liquid through a coffee filter into a bottle. Filter twice to remove any unwanted fat.
**Salted caramel liqueur:
2 cups sugar
2 cups vodka or neutral spirit
Large pinch of salt
Add one cup of the sugar and the salt to a pan over a medium high heat. Allow the sugar to melt and caramelize. Add in the vodka and stir to mix. Return to a low heat and add in the remainder of the sugar while continuing to stir to dissolve any residual solids. Allow to cool and bottle.