Add the cranberries to a food processor and pulse until finely chopped, about the same texture of your crushed pineapple. Place in a large bowl.
12 oz. fresh cranberries
Add the crushed pineapple and sugar to the bowl and stir to combine.
8 oz. crushed pineapple, ¾ cup granulated sugar
Cover and chill for at least 1 hour. Drain off any excess juice.
Using a hand mixer, beat the cream cheese until smooth. Scrape down the sides of the bowl and whisk again until smooth.
4 oz. cream cheese
Pour in the cold heavy cream. Start the mixer on low and mix until incorporated, scraping down the sides of the bowl as needed. Increase the speed and mix until stiff peaks form.
2 cups heavy whipping cream
Fold into the cranberry mixture. Do not overmix, as it will cause the whipped cream to deflate. Add the marshmallows and fold until combined.
3 cups miniature marshmallows
Cover and chill for at least 2 hours before serving.