First, choose a food item or cuisine that interests you. Some will have more information available about them than others, so it's worth doing some investigation before you settle on one. In general, any well known national cuisine will have adequate information available, as will widespread food items like hamburgers, pizza, and sushi.
Once you have selected your topic, you will then do research to see how each of the following geographic concepts affects or is related to your topic:
1. Regions
2. Cultural Landscape
3. Diffusion
4. Distance decay
Be sure to address these specific geographic terms and concepts. You don't need to address them in this order, but you do need to address all of them. You may use "subsets" of these definitions (e.g. contagious diffusion) if such subsets exist. Be sure to refer to your text and glossary to ensure you completely understand these concepts. You should be detailed in your treatment of these concepts - for instance, you should explain both how and why your choice varies by region, and how and why it has been affected by distance decay. Remember that geography, as an academic discipline, seeks to explain why things vary from place to place, not just describe how they do.
Your illustrated paper should be 12 to 15 slides long. You should include a title, an introduction to the topic, a main body that covers how the four geographic concepts relate to your topic, a summary, conclusion, and reference list. You should cite your sources using the citation style appropriate for your field. If you're not sure what that is, use APA style citations. You should use the Notes section of the presentation to include image citations or URLs with the slides on which the images appear.