In a large mixing bowl, combine the softened cream cheese and mayonnaise, stirring until smooth and well combined. Add the lemon juice and vanilla extract, mixing until fully incorporated. This creamy base will bind all the other ingredients together. Gently fold in the drained fruit cocktail, quartered maraschino cherries, and mini marshmallows until evenly distributed throughout the mixture.

In a separate bowl, whip the heavy whipping cream to stiff peaks using an electric mixer—this takes about 2-3 minutes and creates the light, fluffy texture that makes this salad special. Gently fold the whipped cream into the base mixture from Step 1 in two additions, using a spatula and being careful not to deflate the whipped cream. I like to fold gently and deliberately to keep the dessert light and airy rather than dense.

Pour the combined mixture into a 9x13 inch baking dish or similar size, spreading it evenly with a spatula. Cover with plastic wrap and place in the freezer for at least 4-6 hours, or until completely solid. The freezing time allows the flavors to meld and creates the signature firm-yet-creamy texture of this classic dessert.

Remove the frozen salad from the freezer 10-15 minutes before serving to allow it to soften slightly for easier cutting. This brief thawing period makes it much easier to cut into clean squares without the mixture cracking or shattering. Using a sharp knife dipped in warm water between cuts will also help achieve neater squares.