Fill a rocks glass to the top with ice cubes
Pour 0.5 oz of manzanilla sherry, 0.5 oz of Aperol, 0.5 oz of Dubonnet, 0.15 oz of dark cacao liqueur and 1.5 oz of aged rum into a mixing glass
Add 1 dash of rhubarb bitters
Fill the glass with ice cubes and stir gently
Strain into the rocks glass
Garnish with lemon zest