Drain 1 (20-ounce can) crushed pineapple. Use a stainless steel mesh strainer and press to get the excess moisture out. Drain 1 (20-ounce can) pineapple chunks. Set aside.
In a large mixing bowl, use a hand mixer to beat the softened 8 ounces cream cheese, 1/2 cup powdered sugar, and 1 tablespoon cornstarch together until smooth, about 90 seconds.
Add in 1 teaspoon vanilla extract and gradually pour in 1 cup heavy cream Continue to beat until stiff peaks form.
User a rubber spatula to fold in the pineappale and 2 cups mini marshmallows.
Cover the bowl with plastic wrap and refrigerate for 1 hour before serving.