In a large Dutch oven or thick saucepan over medium heat with olive oil, sauté the onions until golden.
Stir in the celery, and cook for another 3 minutes.
Add the beef, and cook until the juices seep out. Season with salt and pepper.
Add the bell pepper, paprika, garlic, tomatoes and bay leaves, and after 1 minute of tossing, add the broth gradually until it is finished, mixing frequently. Let it boil.
Over low heat, let the stew simmer for 2 hours. Cover for the final hour, when the sauce is starting to reduce.
Add the marjoram, lemon zest and caraway seeds. Cook for another 15 minutes.
Add about 1 tablespoon of the potato starch, adjusting the amount according to the thickness desired.
Serve hot on top of freshly cooked polenta.
