In a large bowl add olive oil, paprika, cumin, oregano, salt and pepper. Stir to combine. Add chicken fillets and coat well with the oil and spice mixture.
In a large skillet with a lid, heat 1 teaspoon olive oil and pan fry chicken fillets on one side for 7-8 minutes then turn and continue to cook for another 3 minutes. Transfer chicken to a plate and set aside.
To the skillet, add red onion and cook for a few minutes until soft. Add garlic, tomato paste and if using, add chilli paste. Stir fry for 1 minute, then add zucchini and stock. Simmer for 5 minutes.
Add drained chick peas, stir and return chicken back to the pan. Arrange lemon slices on top of the chicken and place lid onto the skillet. Cook on low to medium heat for 15-20 minutes to allow chicken to fully cook through.
Squeeze the juice of half a lemon over the chicken and garnish with parsley.