How to Make It
In a small saucepan, combine beaten eggs, sugar, and juice of 1 lemon. Stir the mixture constantly over medium heat until boiling; adjust to medium-low heat and continue whisking until mixture has thickened. Remove from the heat, and stir in butter. Cool completely.
In a chilled mixing bowl, beat whipped cream until stiff peaks form. Once your egg "curd" mixture has cooled, fold into whipped cream and set aside.
In a large bowl, add chopped grapes, pineapple chunks, orange segments, bananas, and halved cherries (with stems removed). Stir fruit together until combined. Add mini marshmallows, and mix until incorporated. Toss fruit salad with cream-egg mixture, stirring to coat the fruit evenly and completely.
Cover the bowl with plastic wrap, and let sit overnight (10-12 hours) to let the flavors marry. Serve cold.