Ingredients

1 lb top sirloin, ribeye or NY strip steak, thinly sliced into strips
2 Tbsp olive oil
2 Tbsp unsalted butter
1 small onion, diced
8 oz mushrooms, thickly sliced
2 garlic cloves, minced
1 Tbsp all-purpose flour
1 cup beef broth
3/4 cup heavy whipping cream
1/4 cup sour cream
1 Tbsp Worcestershire sauce
1 tsp dijon mustard
1 tsp salt
1/2 tsp black pepper

Instructions

Place a large deep pan or dutch oven over medium-high heat. Add 2 Tbsp oil and once oil is very hot, add thinly sliced beef strips in a single layer, cooking 1 minute per side without stirring. Cook until just browned and no longer red. Sear beef in batches so you don’t overcrowd the pan. Remove beef to a plate and cover to keep warm.

Add 2 Tbsp butter, chopped onion and sliced mushrooms. Sauté 6-8 minutes or until liquid has evaporated and onions and mushrooms are soft and lightly browned.

Add minced garlic and sauté 1 minute. Add 1 Tbsp flour and sauté another minute stirring constantly.

Pour in 1 cup beef broth, scraping any bits from the bottom of the pan then add 3/4 cup whipping cream and simmer another 1 to 2 minutes or until slightly thickened. Stir a few Tablespoons of the sauce into 1/4 cup of sour cream so the sour cream doesn’t curdle then add it to the pan while stirring constantly.

Stir in 1 Tbsp Worcestershire, 1 tsp Dijon mustard, and season with 1 tsp salt and 1/2 tsp pepper and continue simmering until sauce is creamy. Add beef with any juices back to the pan and bring just to a simmer.