01 - Heat the oil in a large heavy-bottomed pot or Dutch oven over medium-high heat.
02 - Add the onion, red bell pepper, green bell pepper, and jalapeño (if using). Sauté for 5 to 7 minutes until softened.
03 - Add the garlic and cook for 1 minute, stirring constantly.
04 - Add the ground beef and cook, breaking up with a spoon, until browned and no longer pink, about 7 to 8 minutes. Drain excess fat if necessary.
05 - Stir in chili powder, cumin, smoked paprika, cayenne, oregano, salt, black pepper, and sugar. Cook for 1 minute until aromatic.
06 - Add tomato paste, diced tomatoes with juices, and beef stock. Stir to combine thoroughly.
07 - Bring to a boil, reduce heat to low, and simmer uncovered for 30 minutes, stirring occasionally.
08 - Stir in kidney beans and simmer for an additional 15 to 20 minutes until thickened and flavors meld.
09 - Taste and adjust salt, pepper, or heat level as desired.
10 - Serve hot with preferred toppings such as shredded cheese, sour cream, or chopped cilantro.