Place the plastic jello shot cups on a sheet pan without lids; set aside.
Put the powdered Jell-O into a mixing bowl, add the boiling water, and whisk until the gelatin is fully dissolved.
Whisk in the chilled pineapple juice, coconut rum, white rum, and Blue Curaçao until incorporated.
Slowly pour the gelatin mixture into each plastic cup, filling until nearly full.
Move the sheet pan of jello shots to the refrigerator and chill for at least 4 hours, or until completely set. Attach lids to the cups and keep refrigerated until serving time.
Just before serving, pipe a small amount of fresh whipped cream on top and scatter with toasted coconut flakes.
Serve with tasting spoons and enjoy!