Heat olive oil in a large pot over medium-high heat. Brown the beef, breaking it up, 4–5 minutes. Drain excess fat if needed.
Stir in onion and bell pepper. Cook until softened, 3–4 minutes. Add garlic and cook 30 seconds.
Season with chili powder, cumin, smoked paprika, oregano, salt, and pepper. Toast the spices for 30 seconds.
Pour in diced tomatoes, tomato sauce, and beef broth. Scrape the bottom of the pot to release browned bits.
Add macaroni and kidney beans. Bring to a boil, then reduce to a lively simmer. Cover and cook, stirring occasionally, 10–12 minutes, until pasta is al dente.
Uncover and simmer 1–2 minutes to thicken if needed. Adjust salt to taste.
Turn off heat. Fold in cheddar and sour cream until melted and creamy.
Let rest 2 minutes. Serve topped with green onions and a dash of hot sauce, if you like.