Brown the Beef: In a large pot, heat 2 tablespoons of butter over medium-high heat. Brown the beef on all sides, then remove it and set it aside.
Sauté the Vegetables: In the same pot, add the remaining butter. Sauté the chopped onions, carrots, and celery until they soften and begin to caramelize (about 5-7 minutes).
Deglaze the Pot: Add the white wine to deglaze, scraping up any bits from the bottom of the pot.
Add Broth and Spices: Pour in the broth and return the beef to the pot. Add bay leaves, allspice, peppercorns, and salt. Bring to a simmer, cover, and cook on low heat for 1.5 to 2 hours until the beef is tender.
Blend the Sauce: Remove the beef and set it aside. Puree the vegetables and broth using an immersion blender or regular blender until smooth.
Add Cream: Stir in the heavy cream and sour cream. Simmer for 5-10 minutes, adjusting the consistency with water if needed. Taste and add vinegar and sugar to balance the flavors.
Serve: Slice the beef and serve with the creamy sauce. Pair with Czech bread dumplings or boiled potatoes.