What's in a 'Paella'?

Question

Answering this question, I made an ass of myself claiming that

1. Onions are not used in a real Paella.
2. Tomatoes neither.
3. Paprika / Pimentón neither as this will overpower the saffron flavor.

I've seen loads of recipes with all of these ingredients in some way or other (and I posted a recipe with all of these ingredients :-( ).

As I understand it, onions are not used because the will 'pass' the rice. I have no idea whether this is true or not, but I've never eaten a paella with onions. Not that I usually eat paella.

The tomatoes and pimentón will impart too much flavor so it will overpower the saffron taste (by far the most expensive spice on earth). Food coloring can be used to make the paella 'saffron' yellow.

The question is, what defines a real paella? One definition of paella is the 'pan' or 'skillet' itself, meaning that whatever rice dish you make in it can be called paella, but I'd rather have a more 'traditional' view as to what ingredients can or cannot/should or shouldn't be used.

• Onions (yes or no)
• Tomato (yes or no)
• Paprika (no :-)
• Saffron (yes)

Answer

Penelope Casas' The Foods and Wines of Spain explains that

Paella is a word that has come worldwide to mean a Spanish rice dish with a variety of seafood and usually some chicken. However, the word originally referred only to the pan in which the food was cooked--the paella or paellera, from the Latin word for pan, patella. Paellas actually come in endless varieties, depending on the chef and on regional specialties.

She emphasizes the technique more than traditional ingredients (which she notes that no two Spaniards will agree on), but includes recipes for a number of different rice dishes from many regions, all prepared in basically the same manner.

Interestingly, her Paella a la Valenciana (Tradicional) actually doesn't call for saffron (it does call for paprika). The meats are snails and rabbit, and she does call for an onion, but it's only used to steep for a while in the broth, and later discarded. She includes a single tomato which is cooked down with green peppers and garlic. Most of her other paella recipes include onion in this step, but it is notably absent from this recipe. She also calls for lima beans and "wide, flat string beans", and serve the dish with scallions on the side.

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