Roasted Grouper, Tautog, or Rockfish with Mushrooms, Cream, and Mustard
Time requirement: about 20 minutes to make the mushroom duxelles and 20-25 minutes to roast the fish.
What you will need:
1 to ¾ of a pound fish fillet such as grouper, tautog, or rockfish, 1 to 1/14 inch thick.
½ teaspoon kosher salt
½ teaspoon fresh ground black pepper.
8 ounces of button mushrooms.
2 shallots trimmed and peel, about 2 ounces in total weight.
1 tablespoon butter
2 tablespoons light flavored olive oil. (Or other neutral oil such as grapeseed or sunflower oil.)
½ teaspoon of kosher salt.
3 tablespoons heavy cream. Preferably not ultrapasteurized and from a local dairy
1 tablespoon and 1 teaspoon Dijon mustard.
Rinse the fish and pat dry with paper towels. Sprinkle it on each side with the ½ teaspoon each of salt and pepper.
Wash the mushrooms, trim the stems, cut into quarters. Place the mushrooms in a food processor bowl and pulse about 12 times or until you have a bowl of chopped mushrooms. Place the mushrooms in the center of a clean kitchen towel. Bring the corners of the towel together and over the sink twist the towel to extract as much liquid from the mushrooms as possible. Set mushrooms on a plate. Toss then with a pair of forks to fluff them from their crushing in the towel. Set aside.
Cut each shallot into 3-4 pieces and toss them into the the food processor bowl. Process until you have finely chopped shallots (6-7 pulses).
Place the butter and oil in a 10-inch frypan, add the shallot, and heat over a medium heat. When the shallots are bubbling happily in the pan, add the mushrooms and a ½ teaspoon of salt. Cook for 5 minutes stirring frequently.
After 5 minutes add the cream and 1 tablespoon mustard. Cook an additional 2 times. Stir frequently. Scrape the mushrooms onto a plate to cool down. When the mushrooms are a room temperature proceed.
In the meantime, preheat the oven to 400 degrees F. Also line the bottom of a glass or ceramic casserole with parchment paper.
Coat one side of the fish with the 1 teaspoon Dijon mustard. Cut the fish in half for easier serving when it is done.
Place mushrooms in the center of the casserole. Top with the fish, mustard side up. Cover loosely with foil. Cook for 20-25 minutes. That’s it!
Serve the fish atop the mushrooms on warm plates.