No need to open a bottle of wine just to use a small amount in a recipe. Brandy and sherry are good substitutes. They keep indefinitely, once opened, and can then be stored in a cabinet rather than the fridge. In a pinch when baking, brandy can substitute for vanilla extract. But do not use cooking sherry for any purpose; cook with a quality sherry suitable for drinking. All alcohol in cooking should be of a caliber you would like to drink.
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