Pull the husks from the tomatillos and wash them under cool water until they no longer feel sticky. Cut them into quarters and put them into the work bowl of a food processor.

Add the onion and garlic, cilantro, jalapeno and lime juice and process by pulsing until smooth.

Scrape the mixture into a small saucepan. Season lightly with salt and bring to a boil over medium heat. Cook, stirring occasionally, until most of the liquid is boiled off.

The sauce will have the consistency of salsa.

Spice each side of the tilapia.

Heat the oil in a cast iron skillet on medium high heat.

Cook the tilapia 2 minutes per side.

Finish the cooking by heating in a 325 degree oven for 8 minutes.