The art of finishing sauces for fish – The Denver Post

A few weeks ago, a reader wrote to ask if I felt — as she did — that over the past few years onions had been getting “stronger” in both taste and kick. For her, this was true especially for her beloved red onion, something that had been for years touted as “mild” or “sweet,” as onions go.

I didn’t have an answer, but she intrepidly got a hold of the National Onion Association for a  definitive answer. Sure enough, the NOA wrote back to say that “growing things for portability, shelf life, etc.” has contributed to stronger “red and purple onions.”

Who knew? Who knew there was a National Onion Association?

I do know that it’s easy to “sweeten” onions by cooking them for a long time. Their natural piquancy lessens with exposure to heat. In truth, many of the compounds that give onions their blowback caramelize in long cooking. Sulfur turns to sugar.

Mark Bittman’s recipe here today forms a fine bed for grilled fish. It would serve well for other grilled protein, even vegan or vegetarian sorts. When you combine the onions with the liquid exuded by olives and tomatoes, you get a nice Provencal accent.

Simple sauces such as this thick confit aren’t terribly interesting on their own. But neither is a piece of plainly wrought fish. A quick poach, grill, sauté, or bake, even a zap in the microwave, is fine and dandy but wants for more flavor.

Math helps: One simple sauce plus one simple preparation of fish equals buckets of flavor. So try to routinely dress fish dishes with some sort of saucing.

Second only to a mere squeeze of fresh lemon, a trickle of extra virgin olive oil may be the simplest sauce. The best for fish are those unctuous, yellow-green oils from places such as Provence, France, or Liguria, Italy.