Blend the pineapple ice cream base. Add the frozen pineapple chunks, coconut yogurt, coconut milk, and vanilla protein powder to a high-speed blender or food processor. Blend until smooth and creamy.
Fill the pint container. Pour the pineapple mixture into a Ninja Creami pint container, making sure not to go over the max fill line. Place the pint on a level surface before freezing.
Blend the cherry ice cream base. Add the frozen cherries, coconut yogurt, coconut milk, and protein powder or collagen peptides to the blender. Blend until smooth, then pour into a separate Ninja Creami pint container.
Freeze. Freeze both pints for a minimum of 8 hours, or up to 24 hours, until completely solid. For best results, make sure the pints freeze on a level surface.
Spin in the Ninja Creami. Once fully frozen, place one pint container into the outer bowl. Add the outer bowl lid, twist to lock it into place, then place the outer bowl into the Ninja Creami ice cream maker.
Use the Lite Ice Cream function. Power on the Ninja Creami machine and press the Lite Ice Cream button. Once the first spin is complete, the texture will likely look crumbly. That is normal, especially the first time.
Add a splash of milk and respin. Add an additional splash of coconut milk, about 1 tablespoon for a softer soft serve function-style texture or 2 teaspoons for a firmer scoop. Press Respin until creamy. Repeat with the second pint.
Make the swirl. Scoop the pineapple and cherry Dole Whip into a loaf pan in an alternating pattern. Gently swirl with a knife, then freeze for 20 minutes to set.
Serve and enjoy. Scoop into bowls and enjoy your scrumptious ice cream treat immediately. For a more special occasion look, you can also add the mixture to a piping bag and pipe into bowls to create that classic soft-serve ice cream swirl.