Making thumbprint cookies
You can of course use your thumb, but I prefer the end of a wooden spoon or large dowel. It keeps your fingers clean and the indents uniform. Make a well in the cookie before placing them in the oven, again about 10 minutes in to press down any parts that may have puffed up, and once more when the cookies come out of the oven. Do this and you’ll have a perfect “thumbprint” every time.