1 pound firm white mushrooms, cleaned
1 medium lemon
1 tablespoon unsalted butter
2 tablespoons minced shallots
1/4 teaspoon dried thyme
1/2 bay leaf
1 teaspoon salt
1/2 teaspoon freshly ground pepper
2 cups heavy cream
1 1/2 cups chicken stock
1 teaspoon cornstarch, dissolved in 1 tablespoon of water
1 tablespoon minced parsley