Put the ingredients in a mixing glass full of ice and stir to chill. Strain into a double old fashioned glass over a single large ice cube. Twist an orange peel over the surface of the drink and garnish with the peel.
For the pineapple and cinnamon-infused Campari: Peel, core and chop a whole pineapple into 1-2" pieces and place them in a 1-gallon glass container with a tight lid. Gently toast 3 cinnamon sticks in a pan over low heat until warmed and slightly smoky. Add them to the jar along with 1 750-ml. bottle Campari. Let the mixture infuse for 12 hours, then use tongs to remove the cinnamon sticks. Let the mixture infuse another 2 days then strain into a clean glass container.