Adding broth to many recipes is sometimes the most important key to their success. Of course, you can buy ready made broth in tetra pack, or cubes from any supermarket. However, you do not have control over the taste and unhealthy ingredients (e.g. fat and salt) when you do so.
Therefore, making broth of stock at home and freezing them into cubes is a good alternative, both for health and taste.
It is not hard to make broth. You can use the left over bones of chicken, veal, beef, or lamb. The bones can be from cooked meals, or raw. If the bones are raw, it is best to roast them in the oven. If they are left over from a cooked meal, then you don't need to roast them. If you do not have enough bones to make broth, then keep it in a plastic ziplock bag in the fridge for a few days, or in the freezer for longer, until you have enough to make it worthwile to start a stock making session.
The exact measures for the ingredients do not really matter. Experiment until you come up with what works for you.
The overall idea is to add some vegetable ingredients (any combination of onions, carrots and garlic), herbs (any combination of rosemary, thyme, and oregano) and spices to your taste (any combination of cardamom, cumin, coriander, fennel, and allspice). A little salt and black peppter is recommended.
Then you have to simmer the broth for several hours, skimming off the froth from the surface, and letting it reduce so as to concentrate the flavor. Then you strain it and pour it into ice cubes.