In a large skillet, cook ground meat over medium-high heat until no longer pink. Transfer the meat to a bowl. Drain excess grease from skillet, but do not clean.
Add the olive oil to the skillet. Add the onion, green pepper, garlic, parsley and jalapeño peppers (if using) and cook over medium heat, stirring occasionally, until onions are soft and fragrant (about 5 minutes). Remove from heat and add the chili powder, cumin, sugar, oregano, salt, pepper and cayenne pepper. Stir until combined.
If cooking the chili stovetop, add the cooked meat back to the skillet. If using a slow cooker, add meat-veggie mixture to the slow cooker. Add the tomato juice, diced tomatoes, tomato sauce, kidney beans and pinto beans to either the skillet or slow cooker, depending on which you are using. On stovetop, bring to a boil, dial back to medium-low and simmer for 2 hours. In slow cooker, cook on low for 7 to 8 hours. Serve warm with cheese and sour cream.