Heat oil in 10 inch skillet over medium heat until shimmering. Add onion and cook until softened, about 5 minutes. Stir in chili powder, garlic, cumin, coriander, oregano, cayenne and 1 tsp salt and cook until fragrant, about 30 seconds
Stir in ground beef and cook breaking up meat with wooden spoon, until no longer pink, about 5 minutes. Stir in tomato sauce, broth and vinegar and sugar and simmer until thickened, about 10 minutes.
Season with salt to taste.
Divide filling evenly amoung taco shells and serve