Preheat the oven to 180°C / 350°F conventional heat. Finely chop the onion and garlic, and cut the iceberg lettuce leaves into strips.

Heat the oil in a large frying pan. Cook the onion over low heat until soft but not browned. Add the garlic and cook for 1 minute.

Stir in the tomato paste, chili powder, paprika, cumin, coriander, oregano, sugar and 1 tsp salt. Cook over medium heat for 3–4 minutes.

Increase the heat to high, add the ground beef and brown it. Add about 3 tbsp water; the pan should be hot enough for most of the liquid to evaporate. Cook for 5–10 minutes, stirring constantly. Add a little more water if the beef sticks.

Warm the taco shells in the hot oven for 5 minutes.

Put the beef, warm taco shells, iceberg lettuce, grated cheddar and tomato salsa on the table so everyone can fill their own tacos.