cinco de mayo-margaritas and dessert?
Doesn't sound like you're looking for real food / dinner ideas since people will probably have already eaten dinner. If you're looking for wine and cheese ideas, I would include sangria, and definitely do mexican chocolate brownies by adding a little cinnamon and some cayenne pepper to them. I like the Mexican wedding cookie idea, too. Finger foods are probably ideal. If you're looking for something savory, mini empanadas might be good with ground beef, chopped tomato, diced green olives, mexican oregano and raisins for the filling.
A friend of mine from Mexico gave me this recipe (his mother's) for flan - it's one of the more delicious interpretations I've ever had, and so easy!!
1 can sweetened condensed milk
1 can evaporated milk
8 oz. cream cheese, room temperature
1 t. vanilla
1/2 cup sugar
2 T. water
Preheat the oven to 350. With an electric mixer/hand mixer, beat the cream cheese with the condensed milk until smooth, then slowly add the evaporated milk and vanilla, blending well to ensure a smooth consistency. Add the eggs one at a time, blending well with each addition. Set aside.
Place the sugar and water in a saucepan over medium heat and cook until a caramel forms (darken to taste). Pour the caramel into an ovensafe dish (pie plate, casserole, individual ramekins, etc.) and swirl to coat the sides. Pour in the prepared flan mixture. Bake in a water bath for about 1.5 hours (less time if using ramekins) or until a toothpick inserted in the center comes out clean. Allow to cool slightly, invert and refrigerate.
Do you have a grill? I get Mexican-style chorizo (unsmoked) and use it to make a stuffing with breadcrumbs, garlic, tomatoes, onions, and chiles. Then I stuff halved, seeded jalapenos with it, top with a slice of cheese, and grill gently until the peppers are nicely cooked. It works in the oven too, but grill is better.