One recurring question in our cooking classes is how we make the stock we use to make paella. We normally use fish stock when we make paella with any seafood or fish. This post gives you some guidelines on how to make good stock for paella. I say guidelines because there is not a single list of ingredients or invariable process.
In many cookbooks it is called fish “fumet”, that literally means “aroma” in French. Although I recommend having it made before you start preparing the paella, you can also make it on the same cooking season.
For 1.5 liters of stock:
You can add more seafood to make it tastier: mussels, clams, crabs…
You can use similar process to make chicken stock. In that case, use a chicken quarter, sauteing before adding the vegetables. That way, you will get the pan flavoured with the skin fat.