Ingredients:
- 1 lb sirloin steak, thinly sliced against the grain
- 8 oz cremini mushrooms, sliced
- 1 medium yellow onion, finely diced
- 2 cloves garlic, minced
- 2 tbsp unsalted butter
- 1 tbsp vegetable oil
- 2 cups beef broth, low sodium
- 1 tbsp Worcestershire sauce
- 1 tbsp all-purpose flour
- 1 tsp Dijon mustard
- 1/2 cup sour cream, full fat
- salt to taste
- black pepper to taste
Instructions:
- Pat the beef completely dry with paper towels. Season generously with salt and pepper. Note: Dry meat sears, wet meat steams.
- Heat the skillet over high heat with a splash of oil until shimmering. Add beef in a single layer and sear for 60-90 seconds per side until a mahogany crust forms.
- Remove beef immediately to a plate. Note: Do not leave it in the pan or it will toughen.
- Lower heat to medium. Melt the butter and add onions and mushrooms. Sauté 5-7 mins until onions are translucent and mushrooms are golden brown.
- Stir in the garlic and cook for 30 seconds until fragrant.
- Sprinkle in the flour and stir for 1 minute until the raw flour smell disappears.
- Slowly whisk in the beef broth, Worcestershire sauce, and Dijon mustard.
- Simmer for 3-5 minutes until the sauce thickens enough to coat the back of a spoon.
- Turn the heat to low or remove from heat entirely. Stir in the sour cream until fully incorporated and smooth.
- Return the seared beef and any accumulated juices to the pan. Stir gently for 1 minute just to warm the beef.