To a cocktail shaker, add gin, raspberry syrup, lemon juice and egg white. Add on the lid and shake vigorously for 20 seconds.
Add in ice and shake the mixture again until it is thoroughly chilled. Remove the ice from the coupe glass, then strain the drink into the chilled glass.
Decorate the top of the foam with a drizzle of raspberry syrup, or serve with a toothpick speared with fresh raspberries.
Notes
Raspberry Syrup:To make the raspberry syrup: combine 1½ cups raspberries, 1 cup sugar, 1 cup water, and 1½ tsp lemon juice in a saucepan. Simmer 10 minutes, strain well through a fine sieve to remove seeds, and cool completely. Full recipe at raspberry simple syrup.
The dry shake (shaking without ice first) is essential for creating the silky foam layer.
Make your raspberry syrup ahead of time so it's completely cool.
For a vegan version, substitute the egg white with 1/2 oz (15 ml) aquafaba (the liquid from a can of chickpeas). It froths up just as nicely.
This drink is also known as a Clover Club, a classic pre-Prohibition cocktail.
One lemon yields approximately 1 oz (30 ml) of juice.