Add all ingredients, except optional club soda, to a cocktail shaker, and dry-shake for 30 seconds vigorously. This will foam the egg white
Add ice, and shake again for 15–20 seconds
Strain into a chilled glass, or a glass filled with ice
Top with club soda if desired, and garnish with lemon slices or other fruit
Notes
Although this recipe has not been lab tested, a single serving should be low-FODMAP based on the ingredients (using available FODMAP data at time of posting)
1 ounce whiskey is one low-FODMAP serving
You will use about 1/2 lemon for this recipe
Since this recipe does not involve cooking, I recommend pasteurized eggs to reduce bacteria contamination