Heat a large stockpot over medium heat. Cook and stir bacon until lightly browned, 3 to 5 minutes. Stir in onion and garlic. Cook, stirring occasionally, until onion is translucent, 5 to 7 minutes.

Stir in broth, cayenne pepper, salt, and black pepper. Bring to a boil and cook for about 5 minutes. Stir cabbage into the stockpot. Simmer until cabbage has wilted, 10 to 15 minutes. Stir in stewed tomatoes and liquid. Bring soup to a boil; cook for about 5 minutes.

Reduce heat, cover, and simmer, stirring often, for 15 to 30 minutes.