Sauté the shallot and mushrooms in butter until tender. Bring the water to a boil in a saucepan and add the tea bags. Lower to a simmer and steep for 5 minutes. Remove and discard the tea bags. Add the cream to the tea; then whisk in cornstarch. Return to a boil over medium heat until thickened. Then add the mushrooms and shallots and salt and pepper to taste.