Heat the olive oil in a large Dutch oven or heavy-bottomed pot over medium-high heat. Add the ground beef and break it apart with a wooden spoon. Cook for 6–8 minutes until well browned, then drain any excess fat if needed.

Add the chopped onion and red bell pepper to the browned beef. Cook for 4–5 minutes, stirring occasionally, until the vegetables begin to soften. Stir in the minced garlic and cook for another 30 seconds until fragrant.

Add the cumin, smoked paprika, chili powder, coriander, oregano, and a small pinch of cinnamon. Stir everything together and cook for about 1 minute. Toasting the spices first helps bring out a deeper, warmer flavor.

Stir the tomato paste into the beef and vegetable mixture. Cook for 1–2 minutes, stirring frequently, until it darkens slightly. I’ve found this small step gives the finished chilli a richer tomato flavor.

Pour in the chopped tomatoes, beef stock, and Worcestershire sauce. Scrape up any browned bits from the bottom of the pot because they add plenty of savory flavor. Season lightly with salt and freshly ground black pepper.

Bring the mixture to a gentle boil, then reduce the heat to low and partially cover the pot. Simmer for 30–35 minutes, stirring occasionally, until the beef is tender and the tomato sauce becomes thick and rich.

Stir in the drained and rinsed kidney beans. Continue simmering uncovered for another 8–10 minutes so the beans heat through and absorb some of the seasoned sauce without becoming too soft.

Stir in the small piece of dark chocolate until completely melted. It won’t make the chilli taste sweet; instead, it adds depth and balances the acidity of the tomatoes. Taste and adjust the salt, pepper, or chilli powder.

Remove the pot from the heat and stir in most of the chopped cilantro with a squeeze of fresh lime juice. Let the chilli con carne rest for about 5 minutes before serving so the sauce thickens slightly and the flavors settle together.