Depending on the actual recipe, it could be either illicit or invalid. How did Cardinal George know the exact ingredients? Here is a 1979 statement by the Vatican:
"As early as 1979 the Congregation for the Doctrine of the Faith became alarmed over the unauthorized practice in the United States of celebrating Masses with invalid matter and urged its bishops to correct the abuses. On June 4, 1979, Franjo Cardinal Seper, Prefect of the Congregation for the Faith, in a letter directed to Archbishop John R. Quinn, then president of the National Conference of Catholic Bishops, among other important items, the following:
". . . It may be helpful to note that recipes sent to the Sacred Congregation over the past several years vary greatly in the matter of "additions"; where there is question of slight additions (e.g. salt, condiments) the matter will be valid but illicit; where there is question of substitution of all or a large quantity of water by other liquids (e.g. milk, eggs, honey, etc.) the matter will be invalid . . . .It is recommended to the Bishops of the United States that they recall to their priests the need to satisfy any obligation deriving from Masses celebrated with invalid matter. These decisions were approved by His Holiness, Pope John Paul II in the audience of May 11th 1979.12