Make the white chocolate macadamia cold foam. Add heavy cream, white chocolate syrup, whole milk, and 1 tablespoon macadamia nut syrup to a small glass or container and froth with a milk frother for 15-30 seconds. Set aside.
Add the cold brew coffee to a tall glass, then stir in 1 ½ tablespoon macadamia nut syrup. Top with ice.
Pour the cold foam over the sweetened cold brew coffee, then sprinkle with crushed sugar cookies if desired. Drink up!