Add all the ingredients into a mixing glass with ice and stir until well-chilled.
Strain into a chilled coupe.
Garnish with a grapefruit peel and an edible flower.
*Black-pepper-spiced Wray & Nephew rum: In a large container, combine 1/2 oz pink peppercorns and 1/2 oz black peppercorns with 16 oz Wray & Nephew rum, and let sit for 4 to 8 hours. Fine-strain peppercorns out.