Place the frozen pineapple chunks, frozen mandarin oranges, coconut milk, orange juice, and vanilla extract into a high-powered blender or large food processor.

Pulse a few times to break up the large chunks of frozen fruit. Then, turn the machine to medium speed.

If using a blender, use the tamper to push the fruit down into the blades. If using a food processor, stop every 20-30 seconds to scrape down the sides with a silicone spatula. Do not add extra liquid unless absolutely necessary.

Continue blending until the mixture is completely smooth, thick, and creamy, resembling soft-serve ice cream. Taste, and add powdered sugar if desired, blending for 10 more seconds to combine.

Transfer the mixture into a piping bag fitted with a large star tip. Place the piping bag in the freezer for 15-20 minutes to firm up slightly.

Pipe the Dole Whip in a circular, upward motion into cups or bowls. Garnish with a fresh orange slice and a straw. Serve immediately.