Portion out ice cream into a bowl and allow to sit for about 10 minutes at room temperature to soften.
Add frozen pineapple, pineapple juice, and ice cream to the blender.
Blend thoroughly until smooth.
Pour mixture into a shallow dish or bowl and place in the freezer for 40 minutes.
Add semi-frozen pineapple mixture to a piping bag fitted with a star tip.
Pipe Dole Whip into two ramekins or serving dishes. Serve immediately.
Notes
Flash freezing the blended mixture will allow it to get to a consistency that can be piped. If you accidentally freeze it too long and it gets hard, scoop/scrape the frozen mixture out to a pan or dish to soften a little then add to piping bag.
You can optionally add a tablespoon or two of sugar to make it sweeter.