If using cornstarch, mix it with ½ tablespoon water in a small bowl and stir into the cream and milk.
You can substitute dried tarragon, but the flavor will not be nearly as good. Use 1 ½ teaspoons dried tarragon.
This tarragon chicken recipe makes 4 modest servings. If you have very hungry eaters or need to feed more people, consider making 1.5 or twice as many servings. In that case, use an extra-large skillet and fry the chicken in batches.