Heat a saucepan with a little vegetable oil and roast the finely chopped onions in it, so that we get a roasted aroma. The whole thing is extinguished with the broth and simmer for another 15 minutes. Now add the spices and stir well while slowly stirring in the tomato paste. Let the whole thing boil down on a low heat for about 10 minutes.
Finally, season to taste, possibly spice up and thicken with tomato paste or something similar, if necessary.
If you want it sweeter, you can refine it with sugar or sweetener.