Do you like dealing with the public, or are you happier in the kitchen? If you're a people person, choose a food-service business that gives you plenty of opportunity to connect with your customers. If you're not especially gregarious, you'll probably lean more toward a commercial type of business, perhaps a bakery or even a catering service, where you can deal more with operational issues than with people.
Some other types of questions to ask yourself include, Do you have a passion for a particular type of cuisine? Do you enjoy a predictable routine, or do you prefer something different every day? Are you willing to deal with the additional responsibilities and liabilities that come with serving alcoholic beverages?
As you do this self-analysis, think about your ideal day. If you could be doing exactly what you wanted to do, what would it be?
Once you've decided on the best niche for you as an individual, it's time to determine if you can develop a niche in the market for your food-service business.