Ingredients

  • 2 pounds filet mignon or filet mignon tips, cut into thin strips
  • 3 tablespoons unsalted butter
  • 3/4 cup finely chopped onion
  • 1 pound small fresh white mushrooms, caps only, wiped clean and halved
  • 2 1/4 teaspoons all-purpose flour
  • 1/3 cup beef stock or canned broth
  • 1/3 cup heavy or whipping cream
  • 1/2 cup sour cream
  • 2 teaspoons Dijon mustard
  • 1 1/2 tablespoons chopped fresh dill
  • 1 1/2 tablespoons chopped fresh parsley
  • Salt and freshly ground black pepper, to taste

Method

  • Heat a large, heavy skillet, preferably cast iron over high heat.
  • Add the meat, a few pieces at a time, and quickly sear all sides, stirring all the time with a wooden spoon, 3 to 4 minutes.
  • If the meat throws off too much liquid, drain it off and set aside.
  • Remove the meat from the skillet and set aside.
  • Melt the butter in a medium-size skillet over medium heat.
  • Add the onion and saute, stirring occasionally, until softened, about 5 minutes.
  • Increase the heat to medium-high, then add the mushrooms and saute, stirring frequently, until they are deeply colored, about 20 minutes.
  • Turn the heat down to medium-low.
  • Sprinkle in the flour and cook, stirring, for 1 minute.
  • Stir in the stock, heavy cream, sour cream, mustard, and the meat juices, if any.
  • Simmer over low heat until the sauce thickens, about 5 minute; do not allow to boil.
  • Return the meat to the skillet, stir to coat with the sauce, and heat for 1 minute.
  • Stir in the dill, parsley, salt, and pepper, and serve at once.