1 tablespoon vegetable oil, 1 small onion, peeled and chopped fine
In a 12-inch nonstick skillet, heat the oil over medium heat until it’s shimmering, 2 to 3 minutes. Add the onion and cook, stirring occasionally with a wooden spoon, until it’s softened, about 5 minutes.
2 tablespoons tomato paste, ¼ cup taco seasoning
Add the tomato paste and the heaping ¼ cup taco seasoning mixture and cook, stirring often, until the onions are coated and the spices are fragrant, about 1 minute.
1 pound 85% lean ground beef or plant-based ground beef
Carefully add the beef to the skillet. Use the wooden spoon to break the meat into small pieces and mix it with the onions. Cook, stirring occasionally, until the beef is no longer pink, about 5 minutes.
½ cup beef, chicken, or vegetable broth
Stir in the broth and bring the mixture to a simmer (small bubbles will gently break all over the surface). Reduce the heat to medium-low and cook, stirring often, until the liquid has thickened and mostly evaporated but the mixture is still juicy, 8 to 10 minutes. (This is a good time to toast your taco shells! The package will have directions.) Turn off the stove.
12 hard taco shells, toasted
Taste a spoonful of the filling (make sure to cool it down first!) and season the filling with a little extra salt, if desired. Spoon the taco filling into the taco shells and top with your favorite toppings. Just look out for any dragons that might have tried the spicy salsa!