If you already have your own little restaurant and you want to start adding newer and more interesting features to your restaurant to take it to the next level, it is best that you start looking online to find out what it is that the people in your area are looking for. You will be able to find out what is popular and what your town lacks. For example if you look online and find out that there are many burger joints in your town then it is unlikely that you adding burgers to your menu is going to bring in that many more customers. You need to add things to your menu that are unavailable in stores around you and therefore, you will hold a monopoly of that particular product.
However, one thing that always works to bring in customers is to start offering different kinds of internationally blended coffees. Almost everybody drinks coffee and it is something that people buy on impulse instead of on a planned visit. Someone who just happened to be passing by your restaurant en route to work or to pick up their children from school might stop over and pick up a coffee. In fact, you do not even need to commit. You may try it out for a few weeks by looking up coffee machine rental online where you will not need to make a commitment until you are sure that serving coffee will bring in the business that you need.
Good quality espresso machines is not likely to cost you that much money however you are likely to notice that people will walk into your store to buy a coffee on impulse and will tend to accompany that purchase with some food as well. Therefore, selling coffee will not only bring in business through your coffee sales but it will be likely to influence people to buy a lot more than coffee, even if this means a few cookies or a sandwich on the side.
Like coffee, another thing that people would tend to make people walk in on impulse and buy is desert and juice. Consider adding a fresh fruit juice section to your main menu and have posters facing the main road advertising them. This way you may find people walking in on a hot day to buy themselves a cold fruit drink and will likely to accompany that drink with something warm to eat. The trick is to have items that go with each other and to have little package offers.