Preheat oven to 325 degrees F.
Sprinkle beef with salt and let sit for 15 minutes.
Place roasted peppers, paprika and tomato paste in food processor and blend until smooth, scraping down sides a few times to incorporate.
Heat a large Dutch oven to medium-high and add the oil, onions and 1 teaspoon salt. Cook until the onions are golden, about 5 – 8 minutes. Add the blended pepper paste and cook for a couple of minutes.
Add the balsamic vinegar, caraway seeds, beef, carrots, celery, bay leaf and stock. Using a rubber spatula, scrape down the sides of the pot.
Cover the pot with foil and the lid, and transfer to the oven.
Cook until the meat is almost tender, about 2 to 2½ hours, stirring a couple of times during the cooking. Feel free to add a little more stock if it looks like the meat is drying out.
When the meat is tender, remove the pan from the oven and skim off any excess oil and discard the bay leaf. Season with salt and white pepper to taste, stir and fold in the lemon zest, parsley and sour cream and serve with the spätzle, egg noodles or boiled potatoes.