Set a large stockpot (at least 8-quart) over medium-high heat and add the ground beef and diced onion.

Break up the beef with a wooden spoon and cook for 8 to 10 minutes, stirring occasionally, until no pink remains and the onion has softened.

Drain excess grease from the pot, leaving about 1 tablespoon behind for flavor.

Stir in the minced garlic and cook for 1 minute, until fragrant but not browned.

Add the chili powder, cumin, smoked paprika, salt and pepper, and stir for 30 seconds to toast the spices against the hot pan.

Stir in the tomato paste, crushed tomatoes, kidney beans, pinto beans and beef broth, scraping up any browned bits from the bottom of the pot.

Bring the chili to a gentle boil, then reduce the heat to low, cover partially, and simmer for 35 to 40 minutes, stirring every 10 minutes.

Check for doneness: the chili is ready when it has thickened enough to coat the back of a spoon and the beans are tender.

Taste and adjust the seasoning with more salt or chili powder as needed.

Ladle into a slow cooker or large pot set over low heat for serving, and set out bowls of shredded cheddar, sour cream and green onion alongside.