1. In a food processor, purée the black beans, garlic, vinegar, cheddar, cumin, coriander and chili (if using) until smooth, adding a touch of water if needed to make smooth. Season to taste and pour into an oven proof dish. Sprinkle a little extra cheese on top of the dip.
  2. When ready to serve, bake the dip in a 375°F preheated oven until the dip is hot and the cheese fully melted, about 18 minutes. Place onto a lined plate, top with the garnishes and serve with the flatbreads and veggies for dipping.