This is so old fashioned that I am almost embarrassed to post it. It dates from the sixties and was a big part of the hors d'oeuvres tray in big hotels at that time . It consists of mainly root vegetables that are diced and cooked in salt water one by one . They are then plunged into ice cold water to retain their color and allowed to cool. They are then put into a sieve to drain and finally mixed with mayonnaise and a touch of garlic to form a very tasty salad. As you can see here I rolled some slices of ham and filled them with the salad and they were delicious with some tossed greens. You can find many recipes for this on the Internet.