Vanilla extract is not needed to make cookies but it enhances the flavor for sure. Every recipe needs a little seasoning to bring out the flavors from all the ingredients used and vanilla extract does exactly that. You can omit it in any cookie recipe or replace it with something else like almond or hazelnut extract. You can also substitute vanilla extract with the seeds of a vanilla bean or vanilla bean powder: 1 tablespoon vanilla extract = 1 teaspoons vanilla powder 1 tablespoon vanilla extract = 1 teaspoons vanilla seeds