What if I don't have crunchy peanut butter?

The crunchy peanut butter adds crunch and texture to the cookies, since they are lacking in density from not having flour. You can substitute all smooth peanut butter if necessary, but the cookies won't be as good in my opinion.

How can I tell when they're done?

These cookies will puff up as they bake. You'll see the tops crack open, bubble a little, and start to brown. Pull them out when they are just barely brown on top and let them sit for minute, the tops will fall flat in 1-2 minutes.

Can I use natural peanut butter instead?

I really want the answer to this question to be yes, but sadly no you cannot. The consistency is so much different than traditional peanut butter, the cookies won't hold their shape. I tried, several times. I did bake this recipe with Jif Natural peanut butter and it worked well.

Can I freeze the dough?

Freezing the actual cookies will have a better result than freezing the dough. The baked (and cooled) cookies will hold in the freezer for months. Unfortunately, the dough doesn't thaw as well as some flour based doughs do.

What's the best way to store these cookies?

Because they don't have any flour, these cookies are fragile. They'll do best in a very airtight container and you should eat them within the first day or two or freeze them and pull out a couple at a time when you want to eat them. They thaw out in 10 minutes or so.