How do I use my iPad mini as a recipe book?

If you just want to transfer over the PDFs as they are, you can sync them into iBooks:

http://support.apple.com/kb/HT4227

Alternatively, buy one of the several receipe book apps available in the iTunes Store, then use whatever procedure that app provides for importing recipies.

Regards.

Look at this app https://itunes.apple.com/us/app/my-recipe-book-your-recipes/id375811859?mt=8

 Cheers, Tom 😉