01 - Combine frozen pineapple, mango, banana, coconut milk, and lime juice in a blender. Process until completely smooth and creamy, scraping down sides as needed.
02 - Distribute the blended tropical mixture evenly between two tall glasses, filling each about halfway.
03 - Slowly pour 1 cup of chilled lemon-lime soda into each glass, pouring down the side to minimize foam and maintain layer separation.
04 - Place one scoop of vegan vanilla ice cream on top of each float, allowing it to float on the surface.
05 - Decorate with fresh mint leaves, pineapple wedges, and toasted coconut flakes if desired. Serve immediately with straws and long spoons for stirring.