Leave the beans soak overnight, changing the water if you can a couple of times.
Boil the beans until they are soft. This can take anytime between 1-2 hours, depending on how old the beans are. You will need to clear the foam that forms on top.
Drain the beans, but save the water in which they boiled.
Put the beans in a blender, add the minced garlic, a dash of olive oil, and two small ladles of water, and blend well.
If the consistency is too dry, add a little bit more water.
The dip should be creamy.
Meanwhile, cut the red onion into julienne strips, and fry over a low heat.
After around 10 minutes, when the onions are soft, add the tomato paste and the salt. Mix well.
Take the pan off the heat and mix the paprika as well.
Put the dip in a serving bowl, and top with the caramelised onions.
Serve alongside crusty bread.