Add coconut rum, pineapple rum, blue curaçao, and pineapple juice.
Shake for about 10 seconds until cold.
Fill your highball glass with fresh ice.
Strain the mixture into the glass.
Top with lemon-lime soda.
Give it a gentle stir.
Garnish with a pineapple slice.
Notes
Fresh pineapple juice tastes better than canned. Adjust soda sweetness to taste. Increase coconut rum for more coconut flavor. Serve immediately to keep soda fizzy and ice from melting.