In a large pot, melt the butter over medium heat.

Add the chopped onion and minced garlic, cooking until the onion becomes translucent, about 5 minutes.

Stir in the flour to form a roux, cooking for an additional 2 minutes.

Gradually whisk in the chicken broth, ensuring there are no lumps. Bring the mixture to a gentle simmer.

Lower the heat and stir in the heavy cream, mixing well until smooth.

Add the chopped corned beef and drained sauerkraut, stirring until everything is well combined.

Mix in the shredded Swiss cheese and Russian dressing, stirring until the cheese is melted and the soup is perfectly creamy.

Season with salt and black pepper to taste, adjusting as needed.

Let the soup simmer for another 10 minutes so the flavors can meld together.

Serve hot, garnished with rye bread croutons and a sprinkle of chopped parsley.