Scrub and pat dry potatoes. Pierce with a fork. Cook each one at a time in the microwave for about 6-8 minutes, turn over once during cooking. Or, bake in 400 degree oven for about an hour.
Place onions and mushrooms in a microwave safe bowl and cook in microwave for 3-4 minutes or until soft. Drain liquid.
In large, nonstick pan, add the cooked onions and mushrooms, cooked chicken, sour cream, wine, cornstarch, paprika, salt and pepper. Mix well and be sure the cornstarch is dissolved. Bring to a boil. Turn heat down to simmer. Cook uncovered for 10 minutes. Stir often.
To serve: Place 1 potato on each dinner plate. Slice each potato open and mash well, using a fork. Top each with 1¼ cup of stroganoff. If desired, sprinkle each with a little scallions or chives.