Overnight Fruit Salad

I first saw a recipe in my mom's Taste of Home magazine when I was in High School, and it soon became my mom's favorite. I would go home during college breaks and made this just for my mom.
Overnight Fruit Salad

Ingredients
1/4 cup sugar
1/4 cup vinegar
3 eggs, beaten
2 tablespoons butter or margarine
2 cups green grapes
2 cups miniature marshmallows
1 (20 ounce) can pineapple chunks, drained
1 (15 ounce) can mandarin oranges, drained
2 medium firm bananas. sliced
2 cups whipping cream, whipped
1/2 cup chopped pecans

Directions
In a double boiler over medium heat, cook and stir eggs, sugar and vinegar until mixture is thickened and reaches 160 degrees F.
Remove from the heat; stir in butter. Cool.
In a large serving bowl, combine grapes, marshmallows, pineapple, oranges and bananas; add cooled dressing and stir to coat.
Refrigerate for 4 hours or overnight.
Just before serving, fold in whipped cream and pecans.