Heat the olive oil in a large pot over medium heat. Add the onion, carrots, and pepper, and cook for 5-6 minutes or until the onion turns translucent. Transfer the vegetables to a bowl and set aside.
Return the pot to the heat. Add the ground beef and cook for 4-5 minutes or until crumbled and brown.
Stir in the garlic and the reserved onion mixture, and cook for 2-3 minutes, or until the garlic is fragrant.
Stir in the beef broth, beef bouillon (if using), tomato sauce, rice, cabbage, brown sugar, sea salt, black pepper, and bay leaf. Bring to a simmer, then reduce to medium-low and cook with the lid ajar for 20-25 minutes or until the rice is tender. Stir the soup often throughout the cooking time to prevent the rice from sticking.
Remove the bay leaf and discard. Season the soup to taste with salt and pepper and serve hot, garnished with chopped fresh parsley.