Place the meat on a cutting board with the short side towards you and slit it horizontally along the full length about a 1/3 of the way from the top stopping 2 cm from the edge. Fold this part open and slit it again from this side and open it. You now have a long piece of meat.
Mix the garlic in a bowl with the chili powder, cinnamon, cumin, pepper and 1 teaspoon salt. Add the olive oil. Spoon 1 tablespoon of this mixture in another small bowl. Mix the onion and parsley in the mixture in the big bowl.
Preheat the airfryer to 180°C.
Coat the meat with the onion mixture. Roll the meat firmly, start at the short side. Tie the string around the meat at 3 cm intervals. Rub the outside of the rolled meat with the herb mixture.