Remove any fat and tendons from the beef with a sharp knife. Cut the beef into bite-sized pieces (roughly 1.5-2 cm).
Halve 2 of the onions, then cut those halves in half crosswise to create quarters. Halve the other 2 onions and cut into fine rings. Wash the red pepper, remove the stem and seeds, and cut into fine strips.
Thread the beef pieces and coarse onion quarters alternately onto skewers, starting and ending with meat.
Heat the rapeseed oil in a large pan over medium heat until hot. Add the skewers and fry on all sides until browned, about 8 minutes (do not let the temperature rise above medium or the onions will burn). Transfer the skewers to a plate and sprinkle with paprika powder.
Fry the onion rings in the same pan over medium heat, stirring frequently, for about 4 minutes. If they begin to stick, add a splash of water. Stir in the tomato paste and cook for 1-2 minutes. Pour in the pizza tomatoes, ketchup, cola, and brandy. Season with the vegetable broth, paprika powder, freshly ground pepper, curry powder, and salt to taste. Mix in the pepper strips and pickled vegetables.
Return the skewers to the pan and coat them with the sauce.
Cover the pan with a lid, reduce heat to low, and simmer for 2-2.5 hours.
The Boss Kitchen editorial staff oversees content review, fact-checking, and recipe verification across the site. Published articles pass through the editorial team before going live, ensuring ingredient lists, techniques, cooking times, and nutritional claims hold up in a home kitchen. The team coordinates contributions across the site writers, handles reader corrections, and maintains consistency in measurement conventions, safety guidance, and dietary labeling. Posts under this byline typically represent team-reviewed reference material, site announcements, or editorial roundups rather than individual-author features, and they are held to the same sourcing standards as bylined recipe and product coverage.