Thaw and squeeze the spinach until all the water is removed.
Heat heavy cream and butter in a pot until butter melts.
Add the spinach.
Add the seasoning.
Heat until mixture comes to a boil.
Lower to a simmer and cook for at 10 to 12 minutes until the spinach is cooked/tender.
Stir constantly so the spinach does not burn.
In a bowl mix the cold water and cornstarch together.
(Once spinach is cooked, add the cornstarch mixture to the spinach mixture, stirring constantly until mixture begins to thicken.)
Add the parmesan cheese and mix well.
Adjust the seasoning if necessary.