In a large pot over medium heat, melt 2 tablespoons of butter. Add one diced medium onion and sauté for about 5 minutes until it becomes transparent and tender, releasing its sweet aroma. Next, stir in 2 minced garlic cloves and ½ teaspoon of red pepper flakes, cooking for an additional minute until fragrant.

Sprinkle ¼ cup of all-purpose flour over the onion mixture, stirring well to combine. Cook this mixture for about 3 minutes while constantly stirring to prevent burning.

Gradually pour in 40 ounces of chicken broth, scraping the bottom of the pot to ensure nothing sticks. Once combined, add 3 medium diced Yukon Gold potatoes, 1 cup of sauerkraut, 1 tablespoon of Worcestershire sauce, 1 teaspoon of pickling spices, ¼ teaspoon of caraway seeds, and 2 bay leaves. Stir to combine all the flavors.

Increase the heat to bring the pot to a boil, then reduce the heat to a simmer. Allow the soup to simmer uncovered for 12 to 15 minutes, or until the potatoes are fork-tender.

Once the potatoes are tender, remove the 2 bay leaves, and carefully stir in ½ cup of heavy cream. Add in 2 cups of cooked and diced corned beef, folding it gently into the soup to combine all the elements.

Taste your soup and adjust with kosher salt and black pepper according to your preference. For a delightful finish, serve your Creamy Reuben Soup topped with 1 cup of shredded Swiss cheese, letting it melt slightly.