Brown the ground beef in a cast iron skillet over medium-high heat, then drain it before adding to the slow cooker. Cook until the beef is no longer pink and a bit of fond forms at the bottom, about 6–8 minutes (visual: browned crumbles).

Add the chopped cabbage, sliced carrots, sliced celery, diced onion, minced garlic, crushed tomatoes, diced tomatoes, beef broth, Worcestershire sauce, smoked paprika, red pepper flakes, garlic powder, and cumin to the slow cooker, then stir to combine. Mix until the cabbage is evenly distributed and the spices are streaked through the tomato broth (visual: consistent red-orange color).

Cook on Low for 7–8 hours until the cabbage and vegetables are very tender. The soup should look thick and soft around the edges of the vegetables (visual: fork-tender cabbage).

Season with salt and black pepper to taste, stirring once to fully dissolve. The broth should taste balanced and feel thick (visual cue: it coats a spoon).

Serve with green onions and hot sauce. Add toppings right before eating for the freshest finish (visual: bright green onion flecks and a red-hot sauce drizzle).