Start by sautéing the onions and garlic over low/medium heat. Once the onions have become translucent/brown you can add the tomatoes and spices, cook this for another minute. Now add the remaining ingredients and top it off with a cup of water.
You can let it simmer until it has reached your preferred constancy, I leave mine on a low heat for about 30 minutes, make sure to stir every now and then.
Serve with some rice or flat bread, enjoy!