Drain the mandarin oranges and pineapple in a colander for at least 15 minutes, giving them a gentle shake now and then. Drain the cherries, halve them, and pat them dry with paper towels — this keeps the whole salad from turning pink and watery.

If using fresh cream: pour the cold heavy cream into a chilled bowl and beat with the powdered sugar and vanilla until soft, billowy peaks form. If using whipped topping, skip to the next step.

Fold the sour cream into the whipped cream (or whipped topping) until no streaks remain. This is your dressing — taste it; it should be just barely sweet, with a little tang.

In a large bowl, combine the drained fruit, coconut, mini marshmallows and pecans (if using). Pour the dressing over the top.

Fold everything together gently with a big spoon or spatula, lifting from the bottom, until every piece of fruit is coated. Be gentle with the mandarins — they break if you stir hard.

Cover and refrigerate at least 2 hours, or overnight. The marshmallows will soften into the cream and the salad will set up light and fluffy.

Give it one gentle fold, pile it into a pretty glass bowl, set the saved whole cherries on top if you kept any, and serve cold.