Dice the onion and bell pepper into small, even pieces. Mince the garlic. Set aside so everything is ready before you start cooking.

Heat your Dutch oven over medium-high heat. Add the ground beef and cook, breaking it up with your spoon, until deeply browned and crispy in spots - about 8 to 10 minutes. You want some fond (those dark brown bits) stuck to the bottom. Transfer beef to a plate, leaving the fat behind.

Reduce heat to medium. Add onion and bell pepper to the pot with the beef fat. Cook for 5 minutes, stirring occasionally, until softened and starting to turn golden at the edges. Add garlic and cook 1 minute more until fragrant.

Stir in the tomato paste and cook for 2 minutes until it darkens slightly. Add all the spices - chili powder, cumin, smoked paprika, oregano, cayenne, salt, and pepper - and stir constantly for 30 seconds to toast them. Pour in the diced tomatoes with their juice and the beef broth, scraping up every bit of browned goodness from the bottom of the pot.

Return the browned beef to the pot. Stir well, bring to a gentle boil, then reduce heat to low. Cover partially and simmer for 30 minutes, stirring occasionally, until the sauce has thickened and the flavors have melded. The chili should coat the back of your spoon.

Taste and adjust salt as needed - canned tomatoes vary widely. Let rest off heat for 5 minutes to thicken slightly. Serve hot with your favorite low-carb toppings.