Melt the butter in a large pot over medium heat. Add the onions and sauté until tender, about 5 minutes.

Add the garlic and red pepper and sauté an additional minute. Sprinkle the onions with flour, stir to coat, and continue stirring while the flour cooks with the onion for about 3 minutes.

Add the broth and stir to scrape up any bits off the bottom of the pan. Add the potatoes, sauerkraut, Worcestershire sauce, pickling spices, caraway seeds, and bay leaves.

Bring to a boil and then reduce to a simmer for about 12-15 minutes, just until the potatoes are tender. Remove from the heat and remove the bay leaves and any large pieces from the pickling spices.

Stir in the cream. Add the corned beef. Taste and add salt (only if needed) and pepper as needed. Scoop into bowls and top with cheese. Serve with rye bread, if desired.