Partially freeze the beef for easier slicing.

Thinly slice the beef across the grain into bite-sized strips.

In a bowl, combine 2 tablespoons of flour and 1/2 teaspoon of salt.

Coat the beef strips with the flour mixture.

In a large skillet or pot, melt 4 tablespoons of butter over medium-high heat.

Add the sliced mushrooms, chopped onion, and celery to the skillet.

Cook until the vegetables are softened, about 5-7 minutes.

Add the minced garlic and cook for another minute until fragrant.

Remove the vegetables from the skillet and set aside.

Melt the remaining 4 tablespoons of butter in the same skillet.

Whisk in 6 tablespoons of flour to create a roux.

Cook the roux for 1-2 minutes, stirring constantly.

Gradually whisk in 2 cups of water or beef broth (using beef bouillon) until the sauce is smooth and thickened.

Add the sautéed vegetables back to the skillet.

Stir in the beef strips.

Reduce the heat to low, cover, and simmer for 30 minutes, or until the beef is tender.

Stir in the sour cream and Worcestershire sauce.

Heat through gently, but do not boil.

Season with garlic salt to taste.

Serve the beef stroganoff over buttered egg noodles.