How to make:

The butter and condensed milk are first mixed together until completely smooth. The lemon juice and zest is then mixed in. Finally, add in the cornstarch. Do not add the entire amount at once. You may not need it. You only need enough until a very soft dough forms.

The cookies are baked in the oven. Once cooled, you can dust with powdered sugar or leave them plain. Traditionally they are served without any powder sugar. I added powdered sugar because I think it makes them look nicer.

Tips:

• Make sure the butter is completely soft before using. It needs to be soft enough that you can mix it without any lumps. It’s also important that you don’t melt the butter because that will make your mixture too liquidy.
• Add only the amount of lemon juice and zest specified in the recipe. Adding too much will add too much liquid to your cookie dough and your dough will be too wet or you will need to add too much cornstarch to make it solid enough.
• The dough will look softer than typical cookie dough. It should almost look like softened butter. The best way to see if it is ready is to try to roll a piece between your palms. If you can form a ball without the dough completely sticking to your hands, then it’s ready.