Lots, but not all, cookies are kosher. Some cookies contain non-kosher ingredients or are processed on the same equipment as non-kosher products, so it is imperative to purchase cookies that are certified kosher.

In addition, it is preferable to use pat Yisrael products whenever possible. This means that a Jewish person has baked (or assisted in the baking of) the products. Even if he or she simply lights the oven, it is considered as having assisted.

Eating homemade cookies made by a non-Jew with no Jewish involvement is forbidden by halachah, even if they contain only kosher ingredients and perfectly kosher equipment was used.