In a jar, combine the gin, Campari, vermouth, milk, and pineapple juice.
Seal and refrigerate overnight.
The next day, line a mesh strainer with cheesecloth.
Pour the milk-washed mixture through the strainer, allowing the solids to separate.
Discard the solids, gently squeezing the cheesecloth to extract all the liquid.
Repeat the straining a second time.
Pour into coupe or rocks glasses over fresh ice.
Garnish with an orange twist and serve.
