You can cook with any of the Grand Marnier substitutes on our list. However, know that some of them might not work best for the recipe you plan to cook. For instance, the non-alcoholic substitutes might not do great in dishes where the alcohol in Grand Marnier plays an important part. None of the substitutes will completely replicate Grand Marnier, but you can come pretty close by combining brandy with some type of orange flavoring. Orange liqueur such as Cointreau or Curacao work best, but orange concentrate, orange juice, orange zest, or orange extract will also work.