For an extra layer of decadence, consider using chocolate-flavored vodka. Adjust the amount of milk to your preference. For a richer cocktail, use half-and-half or light cream. If you don't have chocolate syrup on hand, a sprinkle of cocoa powder or a drizzle of chocolate liqueur will work nicely. Experiment with different ratios of Frangelico and peanut butter whiskey to find your perfect balance. For a non-dairy option, use almond milk or oat milk as a substitute for the 1% milk.