Fill a mixing glass with ice.
Add gin, sweet vermouth, Campari, lemon juice, and orgeat syrup.
Stir slowly and deliberately for 20–25 seconds until well chilled and properly diluted.
Strain into a rocks glass over a large ice cube.
Express the oils of an orange peel over the surface of the drink, then place the peel on the rim to garnish.
Dropping the white rum sharpens the focus on gin's botanicals and lets the Campari and sweet vermouth relationship - the classic Negroni backbone - shine clearly. The orgeat is used in a near-rinse quantity here, just enough to whisper almond sweetness without pulling the drink into tiki territory; resist the urge to increase it.
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