I'm having some friends over for dinner - there will be 4 people in total. The main course is chicken enchiladas with mexican rice served on the side. The dessert is tres leches. I may also serve a green salad to start. I'm getting hung up on an appetizer (or should I just not worry about having one at all?). I don't want it to be heavy (since the enchiladas and rice will be filling)... any ideas?