Brown the beef: Heat oil in a large pot or Dutch oven. Sear beef cubes on all sides until browned. Remove and set aside.
Build the flavor base: Add onion and garlic to the same pot; sauté until fragrant. Stir in tomato paste and smoked paprika.
Deglaze: Pour in beef broth and scrape up brown bits. Add vinegar, thyme, bay leaf, and carrots. Return beef to the pot.
Simmer: Cover and cook on low heat for 1½–2 hours, stirring occasionally, until beef is tender and sauce is rich and thickened.
Make the cauliflower mash: Steam cauliflower until very soft (8–10 min). Drain well, then blend with butter, cream, garlic, salt, and pepper until smooth.
Serve: Spoon mash onto plates, top with stew, and garnish with fresh parsley.