As you start thinking about your podcast, know that you can download Audacity on your own computers and find help for it here. To convert your podcast to an .mp3, you will need the Lame Encoder. The best way to learn is by diving in and doing it. Practice, and don't wait until the last minute. Feel free to ask questions, and I'll do my best to find answers.
You can listen to a podcast I created for another class. The course was on the general topic of pain.
For podcasts related to food, listen to these samples: Come to My Table, Duck Blind Lessons, There is No Such Thing as Too Much Barbecue, Baking By Senses and Memories, and Just Like Pastrami. Though many of these podcasts are personal, you do not have to get personal. You can get overtly political and talk about your beliefs in those areas. Or you can gather people together to talk about an issue and edit it together into something coherent. If you have any confusion, run your ideas by me.