Step 1.
- Chill a cocktail glass by filling it with ice water and setting it aside.
Step 2.
- In a mixing glass, combine 2.5 ounces of gin and 0.5 ounces of dry vermouth.
Step 3.
- Fill the mixing glass with ice and stir gently for about 30 seconds until well chilled.
Step 4.
- Discard the ice water from the cocktail glass.
Step 5.
- Strain the mixture into the chilled cocktail glass.
Step 6.
- Garnish with one pickled cocktail onion.