Ingredients:

  • 5 lbs Beef Sirloin or Tenderloin, cut into thin strips
  • Kosher Salt, To taste
  • Freshly Ground Black Pepper, To taste
  • 2 Tbsp All-Purpose Flour
  • 2 Tbsp Unsalted Butter, divided
  • 1 Tbsp Olive Oil
  • 1 medium Yellow Onion, finely diced
  • 8 oz Cremini (Baby Bella) Mushrooms, sliced thickly
  • 2 cloves Garlic, minced
  • 1/4 cup Dry Sherry or Dry White Wine (Optional)
  • 1 1/2 cups Low Sodium Beef Broth
  • 1 Tbsp Worcestershire Sauce
  • 1 tsp Dijon Mustard (smooth variety)
  • 1 Tbsp Cold Unsalted Butter, cut into small pieces
  • 1 cup Full Fat Sour Cream, at room temperature
  • 2 Tbsp Fresh Parsley, chopped (For garnish)
  • Cooked Egg Noodles or Rice, for serving

Instructions:

  1. Pat the beef strips thoroughly dry with paper towels. Toss lightly in a bowl with the flour, salt, and pepper until just coated.
  2. Heat 1 Tbsp butter and 1 Tbsp oil in a large skillet over medium-high heat until shimmering. Sear the beef in small batches (do not overcrowd the pan!) for 1-2 minutes per side until well browned. Remove immediately with a slotted spoon and set aside on a clean plate. Add the remaining 1 Tbsp of butter to the hot pan after all the beef is seared.
  3. Reduce heat to medium. Add the diced onion to the skillet and sauté for 4-5 minutes until softened.
  4. Increase heat slightly. Add the sliced mushrooms and cook, stirring occasionally, until they have released their moisture and started to brown deeply (about 6-8 minutes). Add the minced garlic during the last minute.
  5. Pour in the Sherry/Wine (if using). Scrape up any browned bits stuck to the bottom of the pan and let the liquid reduce by half.
  6. Stir in the beef broth, Worcestershire sauce, and Dijon mustard. Bring the mixture to a gentle simmer. Return the seared beef and any accumulated juices to the skillet. Simmer gently for 5 minutes.
  7. Remove the skillet entirely from the heat. In a separate small bowl, whisk about 1/2 cup of the warm sauce mixture into the room-temperature sour cream to temper it.
  8. Pour the tempered sour cream mixture back into the skillet, stirring gently until the sauce is uniformly creamy. Whisk in the final 1 Tbsp of cold butter, piece by piece, for extra sheen. Taste and adjust seasoning.
  9. Serve immediately spooned generously over hot, buttered egg noodles and garnish with fresh parsley.