• Heat olive oil in a large, heavy-bottomed pot or Dutch oven over medium heat.
• Add the chopped onions and cook for 2-3 minutes until they start to soften.
• Add the bell pepper and minced garlic and cook for an additional 2 minutes.
• Stir in the chili powder, cumin, paprika, dried oregano, cayenne pepper, salt, and black pepper.
• Add the ground beef to the pot and break it apart with a spoon. Cook, stirring frequently, until the beef is browned and cooked through, about 5-7 minutes.
• Add the tomato puree, and canned diced tomatoes (with their juices). Stir to combine.
• Pour in the beef or vegetable broth, and bring the mixture to a boil.
• Reduce the heat to low, cover the pot with a lid, and let the chili simmer for at least 30 minutes, stirring occasionally. You can let it simmer longer if you have the time, as this will deepen the flavors.
• Taste the chili and adjust the seasoning with more salt, pepper, or cayenne pepper if needed to suit your taste. Stir in the kidney beans and heat for a further 5 minutes.
• Serve the chili hot in bowls, and top each serving with shredded cheddar cheese, a dollop of sour cream, chopped green onions, sliced jalapeños, and fresh cilantro if desired.

Slow Cooker Method:

• Brown the ground beef and transfer it to the slow cooker.
• Sauté onions, garlic, and bell pepper in a pan, then add them to the slow cooker.
• Stir in the broth, chili powder, cumin, paprika, dried oregano, cayenne pepper, salt, black pepper, tomato puree, canned diced tomatoes, in the slow cooker.
• Cook on low for 6-8 hours or high for 3-4 hours.
• Stir in the kidney beans and heat for a further 5 minutes.

Instant Pot Method:

• Brown the ground beef in the Instant Pot.
• Sauté onions, garlic, and bell pepper in the Instant Pot.
• Stir in the broth, chili powder, cumin, paprika, dried oregano, cayenne pepper, salt, black pepper, tomato puree, canned diced tomatoes, to the Instant Pot.
• Pressure cook on high for 15-20 minutes.
• Allow natural pressure release.
• Stir in the kidney beans and let them warm through.