Will brownies and cookies still taste good after they have been refrigerated?
I am in school to be a pastry chef, as above said they will eventually go stale, but for overnight or for a day or two they should be fine. If they are a little dry and hard, put them in a paper bag that you sprinkle with water on the inside, and the bag will steam them back to life. The airtight container isn’t really that much of a help because it is the cold of the refrigerator that makes the cookies/brownies harden, and even inside an airtight container moisture can form and make the cookies/brownies go stale. I say if you really want to preserve your cookies and brownies for a number of days, or for a week or more, put them inside the freezer in freezer bags. Make sure all the air is squished out, and they should be just fine when you pull them out and let them thaw, or defrost them in the Microwave.