The best burgers in the world can be found in the streets of Santo Domingo. They are called Chimichurri. (Btw. Chimichuri in Argentinia is a sauce for steaks.)
As long as you have a firm stomach, you know, one that can handle food from the streets of developing countries, I would highly recommend eating this! Of course this is nothing for vegetarians...
It contains bun, cabbage, carrots, onions, lettuce, tomatoes, meat, cheddar cheese, bacon, and lots of ketchup and mayo... There's also some undefined sauce. It's definitely an explosion for the senses of taste and smell.
Every time, I come to the Dominican Republic, I need to eat this. My stomach has been trained by the night markets of Taiwan since childhood. But even I have standards. I only buy from people that look relatively clean and who have some kind of organization. Cooling boxes are a big plus, while flies and cockroaches ar a big no go... Pretty self-explanatory, right?
I would say, this is better than what some gourmets offer in their high class restaurants. Btw, it's something Anthony Bourdain missed out, when he filmed in the Dominican Republic. I love his tv serie, although it always makes me hungry (for food and travel)... ;-)