With such a simple cocktail, each ingredient makes a huge difference. There is only one campari, but when it comes to gin go for a nice juniper forward gin, and when it comes to sweet vermouth Carpano Antica Formula Sweet Vermouth can't be beat. Or try punt-e-mes for a slightly more bitter and less sweet take. Again, with such a simple cocktail, always feel free to tweak the ratios or if you are ike me - turn it into a Negroni Sour - see below for the negroni recipe.
1 oz of your favorite gin
1 oz Campari
1 oz sweet vermouth
Garnish: orange peel
30 ml of your favorite gin
30 ml Campari
30 ml sweet vermouth
Garnish: orange peel
250 ml of your favorite gin
250 ml Campari
250 ml sweet vermouth
Garnish: orange peel
Place all liquid ingredients in a stir tin with ice. Stir vigorously until chilled. Strain into low ball glass with a single fresh cube or ball ice cube. Express orange peel over rim, and garnish with peel.