At one time, Thompsons were the No. 1 table grape, raisin grape and wine grape in California. In a way, that very ubiquity became the Thompson's downfall. After so long at the top of the heap, they became generic.
In some cases, that was justified: A Thompson Seedless picked green is about as innocuous as a grape can be. But given a chance to ripen, a Thompson can become a pretty danged good piece of fruit. Choose them when they're really ripe and you'll be surprised at how floral and sophisticated their flavor can be.
How to choose: Thompsons don't start to get really delicious until the color turns golden, almost amber. Don't be discouraged if the grapes shake off their stems avoiding this problem (called "shatter" in the business) is part of what prompted early picking in the first place.
How to store: Keep grapes in the coldest part of the refrigerator wrapped in a perforated plastic bag that will allow excess moisture to escape.
How to prepare: At their best, Thompsons have a flowery quality, almost like Muscats. These are best with creamy soft cheeses such as Taleggio.