Add 1 Tablespoon chicken bouillon to the cold water in the pot. You may also add herbs/spices if you wish.
Cook pasta according to package directions. Start checking about two minutes before the end of cooking time. Add a cup of cold water to stop cooking as soon as pasta is ready (a bit beyond al dente ... firm ... because the pasta won't continue to cook in sauce but NOT soft or soggy!)
Drain pasta and rinse. While still warm, add up to an entire bottle of Italian dressing and cooked veggies. Toss well and refrigerate in covered container to let pasta and veggies absorb flavors of dressing.
About an hour before serving, add enough mayonnaise to create desired creamy texture. Add a moderate amount at a time since the pasta will have absorbed the Italian dressing and need a fraction of the usual amount of mayonnaise.
If you can find grape tomatoes at the supermarket, wash them and add them after the mayonnaise for color and extra flavor.
Choose two serving dishes. Divide the pasta salad in half and garnish each half with radish roses, multi-color pepper rings, etc. Refrigerate until it's time to serve. Take one serving dish out of the refrigerator and place in a larger dish full of crushed ice.
As guests get near the bottom of the first dish, replace the ice and place the second serving dish inside.