Ingredients:

  • 1.5 lb (700g) beef sirloin steak, trimmed of excess fat and cut into ¼-inch thick strips (about 2cm)
  • 2 tablespoons (30ml) olive oil
  • 1 medium yellow onion, finely chopped
  • 2 cloves garlic, minced
  • 8 oz (225g) cremini mushrooms, sliced
  • 1 teaspoon (5ml) dried thyme
  • 1/2 teaspoon (2.5ml) smoked paprika
  • Salt and freshly ground black pepper to taste
  • 4 tablespoons (60g) unsalted butter
  • 1/4 cup (30g) all-purpose flour
  • 2 cups (475ml) beef broth (low sodium preferred)
  • 1/2 cup (120ml) dry sherry or dry white wine (optional, but adds a nice depth)
  • 1 tablespoon (15ml) Worcestershire sauce
  • 1 teaspoon (5ml) Dijon mustard
  • 1 cup (240ml) sour cream (full fat is recommended for the best flavour and texture)
  • 2 tablespoons (30ml) chopped fresh parsley, for garnish

Instructions:

  1. Season beef strips with salt, pepper, thyme, and smoked paprika.
  2. Heat olive oil in a large skillet over medium-high heat. Sear the beef in batches, ensuring not to overcrowd the pan, until browned on all sides. Remove beef from the skillet and set aside.
  3. Add onion and garlic to the skillet and sauté until softened and fragrant. Add the mushrooms and cook until tender and slightly browned.
  4. Melt butter in the skillet. Whisk in flour and cook for 1-2 minutes until a smooth paste forms (a roux).
  5. Gradually whisk in beef broth and sherry (if using) to the roux, scraping up any browned bits from the bottom of the pan. Add Worcestershire sauce and Dijon mustard. Bring to a simmer and cook until the sauce has thickened slightly.
  6. Return the beef to the skillet. Reduce heat to low and gently stir in the sour cream. Heat through, being careful not to boil (or the sauce will curdle!).
  7. Garnish with fresh parsley and serve immediately over egg noodles, rice, or mashed potatoes.