Brown beef with onion in a large deep skillet or pot over medium-high about 6-7 minutes until meat is cooked through and onion softened.
Add garlic, chili powder, cumin, paprika, salt, and pepper; cook 1 minute until fragrant.
Stir in tomatoes with chiles, tomato sauce, and broth; break spaghetti in half and add, pushing into liquid.
Boil, then reduce heat to medium-low; simmer uncovered 12-15 minutes until pasta is tender and most liquid absorbed, stirring occasionally.
Remove from heat; stir in cheddar until melted.
Serve topped with sour cream and crushed chips.