- 30ml of whisky (Scotchbox use a Cask Strength Glengoyne, but feel free to use what you have)
- 30ml of simple syrup
- 30ml of lemon juice
- One egg white (optional)
Chill a coupe glass in the freezer.
Combine all of the ingredients in a shaker and dry shake for one minute.
Add a few ice cubes and shake again for another minute.
Double strain over your glass and garnish with a dash of bitters.
Notes: To adjust the sour you can add more of less of the lemon juice or simple syrup. Just make sure the total amount of liquid is 90ml.
The egg white is just to make it foam and is optional.