Make-Ahead: The mold can be prepared up to 2 days ahead.
You will need a 6-cup mold for this salad. A metal ring mold will do, but Jell-O makes a beautifully designed plastic one that I am very partial to. The "Holiday Ring Mold" is available in some supermarkets during the holidays, or by mail order through the Jell-O web site, www.jell-o.com (go to the "Corner Store," and look for the "Jell-O Molds" section.)
This recipe is easily halved again fill a 9-cup mold (use three 3-ounce packages of Jell-O), or doubled to fit a large mold. Just be sure that the Jell-O mixture comes to the top of the mold, or it will be difficult to unmold.
As easy as it is, there are tips to make a good Jell-O mold. First, be sure the gelatin is completely dissolved, which takes 2 minutes of constant stirring. Don't cheat, or the mold won't set properly.
The Jell-O must be partially set in order to support the weight of the added fruit or the chunks will sink to the bottom of the mold. You can chill it in the refrigerator for about 1 1/2 hours, but chilling in an ice-water bath cuts the time, and allows you to keep an eye on the progress.
You should have 3 cups of combined orange segments, grape halves, and sliced strawberries for this salad. The exact proportion of each fruit doesn't matter, and you can add other fruit, such as raspberries, peeled, cored and diced apple or pear, or cubed bananas, if you wish.
2. Meanwhile, grate the zest from one orange and set aside. To cut all of the oranges into segments, use a serrated knife to cut the tops and bottoms from each orange. Following the curve of each orange, cut off the thick white pith where it meets the orange flesh. Working over a bowl, cut between the thin membranes to release the orange segments, letting them drop into the bowl. Drain the oranges before using.
3. Stir the orange segments, orange zest, grapes, and strawberries into the partially set Jell-O. Lightly spray a 6-cup decorative mold with nonstick vegetable spray. Pour the Jell-O into the mold and cover with plastic wrap. Refrigerate until set, at least 4 hours or overnight.
4. To unmold, run a knife around the inside edge of the mold to break the "seal." Lightly moisten a serving platter (this will allow you to move the unmolded salad on the platter, if you need to.) Place the platter upside-down over the top of the mold. Holding the mold and platter together, invert and shake firmly to unmold the salad. If the salad doesn't unmold, dip the outside of the mold briefly (less that 5 seconds) in a bowl of warm tap water. Dry the outside of the mold and try again. Serve chilled.
